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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2020.2150 Squid Proxy Cache Security Update Advisory 22 June 2020 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Squid Proxy Publisher: Squid Operating System: UNIX variants (UNIX, Linux, OSX) Windows Impact/Access: Denial of Service -- Remote/Unauthenticated Resolution: Patch/Upgrade Original Bulletin: http://www.squid-cache.org/Advisories/SQUID-2020_5.txt http://www.squid-cache.org/Advisories/SQUID-2020_6.txt - --------------------------BEGIN INCLUDED TEXT-------------------- __________________________________________________________________ Squid Proxy Cache Security Update Advisory SQUID-2020:5 __________________________________________________________________ Advisory ID: | SQUID-2020:5 Date: | June 19, 2020 Summary: | Denial of Service when using SMP cache Affected versions: | 5.0.1 -> 5.0.2 Fixed in version: | 5.0.3 __________________________________________________________________ <http://www.squid-cache.org/Advisories/SQUID-2020_5.txt> <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14059> <https://github.com/squid-cache/squid/security/advisories/GHSA-w7pw-2m4p-58hr> __________________________________________________________________ Problem Description: Due to an Incorrect Synchronization, Squid is vulnerable to a Denial of Service attack when processing objects in an SMP cache. __________________________________________________________________ Severity: This problem may allow a remote client to trigger a Squid worker assertion. This attack is limited to SMP Squids using shared memory cache and/or an SMP rock disk cache. CVSS Score of 7.3 <https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C/CR:X/IR:X/AR:H/MAV:N/MAC:H/MPR:L/MUI:N/MS:C/MC:N/MI:X/MA:H&version=3.1> __________________________________________________________________ Updated Packages: This bug is fixed in Squid version 5.0.3. In addition, patches addressing this problem for the stable releases can be found in our patch archives: Squid 5: <http://www.squid-cache.org/Versions/v5/changesets/squid-5-7a5af8db8e0377c06ed9ffbdcb1334389c7cd8ab.patch> If you are using a prepackaged version of Squid then please refer to the package vendor for availability information on updated packages. __________________________________________________________________ Determining if your version is vulnerable: All Squid-3.x up to and including 3.5.28 are not vulnerable. All Squid-4.x up to and including 4.12 are not vulnerable. Squid-5.0.1 and 5.0.2 not using SMP caching are not vulnerable. Squid-5.0.1 and 5.0.2 using SMP caching are vulnerable. __________________________________________________________________ Workarounds: Disable all SMP caching. For example: * If using multiple Squid workers, set 'cache_mem' to '0' and remove all `cache_dir` directives from squid.conf. * If using a single Squid worker, remove all 'cache_dir rock' directives from squid.conf. __________________________________________________________________ Contact details for the Squid project: For installation / upgrade support on binary packaged versions of Squid: Your first point of contact should be your binary package vendor. If your install and build Squid from the original Squid sources then the <squid-users@lists.squid-cache.org> mailing list is your primary support point. For subscription details see <http://www.squid-cache.org/Support/mailing-lists.html>. For reporting of non-security bugs in the latest STABLE release the squid bugzilla database should be used <http://bugs.squid-cache.org/>. For reporting of security sensitive bugs send an email to the <squid-bugs@lists.squid-cache.org> mailing list. It's a closed list (though anyone can post) and security related bug reports are treated in confidence until the impact has been established. __________________________________________________________________ Credits: This vulnerability was discovered by Jack Zar of Bloomberg. Fixed by Alex Rousskov of The Measurement Factory. __________________________________________________________________ Revision history: 2020-03-02 16:45:44 UTC Initial Report 2020-05-13 06:37:31 UTC Patch Released - ------------------------------------------------------------------------------- __________________________________________________________________ Squid Proxy Cache Security Update Advisory SQUID-2020:6 __________________________________________________________________ Advisory ID: | SQUID-2020:6 Date: | June 19, 2020 Summary: | Denial of Service issue in TLS Handshake Affected versions: | Squid 3.1 -> 3.5.28 | Squid 4.x -> 4.11 | Squid 5.x -> 5.0.2 Fixed in version: | Squid 4.12 and 5.0.3 __________________________________________________________________ <http://www.squid-cache.org/Advisories/SQUID-2020_6.txt> <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14058> <https://github.com/squid-cache/squid/security/advisories/GHSA-qvf6-485q-vm57> __________________________________________________________________ Problem Description: Due to use of a potentially dangerous function Squid and the default certificate validation helper are vulnerable to a Denial of Service attack when processing TLS certificates. __________________________________________________________________ Severity: This problem allows a trusted client to perform Denial of Service when opening TLS connections with a server for HTTPS. This problem allows a trusted client to perform Denial of Service when opening TLS connections to a server for SSL-Bump intercepted transactions. This attack is limited to Squid built with OpenSSL features and opening peer or server connections for HTTPS traffic and SSL-Bump server handshakes. CVSS Score of 8.3 <https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:F/RL:O/RC:C/CR:X/IR:X/AR:H/MAV:N/MAC:H/MPR:N/MUI:X/MS:C/MC:N/MI:N/MA:H&version=3.1> __________________________________________________________________ Updated Packages: This bug is fixed by Squid versions 4.12 and 5.0.3. In addition, patches addressing this problem for the stable releases can be found in our patch archives: Squid 4: <http://www.squid-cache.org/Versions/v4/changesets/squid-4-93f5fda134a2a010b84ffedbe833d670e63ba4be.patch> Squid 5: <http://www.squid-cache.org/Versions/v5/changesets/squid-5-c6d1a4f6a2cbebceebc8a3fcd8f539ceb7b7f723.patch> If you are using a prepackaged version of Squid then please refer to the package vendor for availability information on updated packages. __________________________________________________________________ Determining if your version is vulnerable: All Squid-2.x up to and including 2.7.STABLE9 are not vulnerable. All Squid-3.x up to and including 3.4.14 built without --enable-openssl are not vulnerable. All Squid-3.x up to and including 3.4.14 built with --disable-openssl are not vulnerable. All Squid-3.x up to and including 3.4.14 built with --enable-openssl are vulnerable. All Squid-3.5 up to and including 3.5.28 built without --with-openssl are not vulnerable. All Squid-3.5 up to and including 3.5.28 built with --without-openssl are not vulnerable. All Squid-3.5 up to and including 3.5.28 built with --with-openssl are vulnerable. All Squid-4.x up to and including 4.11 built without --with-openssl are not vulnerable. All Squid-4.x up to and including 4.11 built with --without-openssl are not vulnerable. All Squid-4.x up to and including 4.11 built with --with-openssl are vulnerable. Squid-5.0.1 and 5.0.2 built without --with-openssl are not vulnerable. Squid-5.0.1 and 5.0.2 built with --without-openssl are not vulnerable. Squid-5.0.1 and 5.0.2 built with --with-openssl are vulnerable. __________________________________________________________________ Workaround: * For interception proxies using SSL-Bump functionality there is no workaround. * For reverse-proxy the GnuTLS support available in Squid-4 may provide sufficient functionality. The vulnerable certificate validator helper feature is not supported yet by GnuTLS builds. * Other installations just needing to relay HTTPS do not need OpenSSL support and should be able to run a build that does not have --with-openssl. __________________________________________________________________ Contact details for the Squid project: For installation / upgrade support on binary packaged versions of Squid: Your first point of contact should be your binary package vendor. If you install and build Squid from the original Squid sources then the <squid-users@lists.squid-cache.org> mailing list is your primary support point. For subscription details see <http://www.squid-cache.org/Support/mailing-lists.html>. For reporting of non-security bugs in the latest STABLE release the squid bugzilla database should be used <http://bugs.squid-cache.org/>. For reporting of security sensitive bugs send an email to the <squid-bugs@lists.squid-cache.org> mailing list. It's a closed list (though anyone can post) and security related bug reports are treated in confidence until the impact has been established. __________________________________________________________________ Credits: This vulnerability was discovered by Dimitra Azariadi and Mario Galli of Open Systems AG. Fixed by Christos Tsantilas of The Measurement Factory. __________________________________________________________________ Revision history: 2020-03-04 09:31:23 UTC Initial Report 2020-05-15 04:54:54 UTC Patches Released - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBXvAbhuNLKJtyKPYoAQhR0w/+M+5AYSs6fu1RXFjqdDpytA5lAIQEfPS3 Bc/EoVY9G5eGIGFfxXMtBrLha9uuy3WnnGCDt1s79aGAh/I15wDbHu/wJambekbx 8YEX1Ebb50M8WMVQvzY1I3NwydWPnwuFYrtls8TxSyot7284mi3T9kKZEiEO2bqM 06QeZxAvK28zF6wBkm6Wo2+6EXdUbYFpspsMjiUTALtLot1d5sqKfc3P9GqUpGty sYskKSp+yPSDIUji5MFzGPVH7QCRmjAWjVUxcjmMRLMk5EpYlxB/0C9Iv0s3TA9y PZQrlqoTQUMCfOPAKi/lobiWbKQAP4aMJsrq9+Eg9IFLZqhxRLB/v2DXYFH+HWHu kfgbB3cH4hbotTJvNYAvRW+n//UZeb3Jj15jLqk29+jD/Fq6/fctnW8/Q6R5LfCS 1celr2b6VAZ+zsXQ0VpetrmpwrEagzjcCTLD0iUD4kvuYYxYKkzEdE8YZG9XmhXe s9z9S+kwciJRBFhvk4ddAJB25XckM7FNxspArtaiebttf8gCUfZI10a5Q9DOhLgU UNBpJHdEmZ4p4xbG9UNnVjnNSJbKPu5Khf6VquRNpIAYCBkfpIdpJWI09+pvESnQ 8A0ctGNTsi01SoNVGqR+5LxBSr4IMiKquFu2qH/8RYnHuaT+aBj9T03bGN4HLPQ/ 5ys3cikEfhE= =QfbR -----END PGP SIGNATURE-----