What’s Vulnerable › Vulnerabilities

CVE-2020-15049

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 5.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-06-30 · updated 2026-06-17
• Weakness: CWE-444

Description

An issue was discovered in http/ContentLengthInterpreter.cc in Squid before 4.12 and 5.x before 5.0.3. A Request Smuggling and Poisoning attack can succeed against the HTTP cache. The client sends an HTTP request with a Content-Length header containing "+\ "-" or an uncommon shell whitespace character prefix to the length field-value.

Affected products

• Fedoraproject Fedora: 31
• Squid: from 2.0 through 2.6; from 3.1 through 3.5.28; from 4.0 before 4.12; from 5.0 before 5.0.3; 2.7, 2.7-stable2, 2.7-stable3, 2.7-stable4, 2.7-stable5, 2.7-stable6 (+3) — fixed in 4.12, 5.0.3

How to fix

Upgrade to a fixed version: Squid 4.12, 5.0.3. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html
• http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html
• http://www.squid-cache.org/Versions/v4/changesets/squid-4-ea12a34d338b962707d5078d6d1fc7c6eb119a22.patch
• http://www.squid-cache.org/Versions/v5/changesets/squid-5-485c9a7bb1bba88754e07ad0094647ea57a6eb8d.patch
• https://github.com/squid-cache/squid/security/advisories/GHSA-qf3v-rc95-96j5
• https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3RG5FGSTCAYVIJPJHIY3MRZ7NFT6HDO7/
• https://security.netapp.com/advisory/ntap-20210312-0001/
• https://usn.ubuntu.com/4551-1/
• https://www.debian.org/security/2020/dsa-4732
• http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html
• http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html

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