CVE-2026-33526
No exploitation reported by the sources we read.
- Published2026-03-26
- Fixed in7.5
- WeaknessCWE-416 · CWE-825 · CWE-826
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Squid is a caching proxy for the Web. Prior to version 7.5, due to heap Use-After-Free, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.
Timeline
dates in UTC- 2026-03-2601:16CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-33526?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-33526?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 7.5 | < 7.5 | 7.5 | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Packages
- libecapAlmaLinux:8all versions · fixed in 1.0.1-2.module_el8.6.0+2741+01592ae8and 1 other package
- libecapAlmaLinux:8all versions · fixed in 1.0.1-2.module_el8.6.0+3048+383bc947and 1 other package
- squidAlmaLinux:10all versions · fixed in 7:6.10-6.el10_1.3
- squidAlmaLinux:9all versions · fixed in 7:5.5-22.el9_7.4
- squidAlmaLinux:8all versions · fixed in 7:4.15-10.module_el8.10.0+4163+e77fcdac.11
Fix
- Update Squid-cache squid to 7.5
Advisories and patches
- github.comPatch
- github.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 4.0 vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Published
- 2026-03-26
- Last Modified
- 2026-07-15
- NVD status
- Modified
Frequently asked questions
What is CVE-2026-33526?
Is CVE-2026-33526 actively exploited?
What is the CVSS score for CVE-2026-33526?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.