CVE-2026-33526

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 8.9%, top 5% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 9%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

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.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
52(Track)
EG Risk 52/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation9% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
9%
EPSS %ILE
95%
KEV
Not listed

Published

March 26, 2026

Last Modified

July 15, 2026

Advisory Details (10)

Auto-updated Jul 3, 2026
Patch available. Sources: github_commit, github, redhat.
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions and Red Hat Enterprise Linux 8.8 Telecommunications Update Serv

https://access.redhat.com/errata/RHSA-2026:20580
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Update Services for SAP So

https://access.redhat.com/errata/RHSA-2026:20565
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support

https://access.redhat.com/errata/RHSA-2026:20564
redhat Patch Available

Affected: Red Hat Enterprise Linux 10.0 Extended Update Support.

https://access.redhat.com/errata/RHSA-2026:11901
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions.

https://access.redhat.com/errata/RHSA-2026:10257
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions.

https://access.redhat.com/errata/RHSA-2026:10256
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.4 Extended Update Support.

https://access.redhat.com/errata/RHSA-2026:10255
generic Patch Available

oss-security - [ADVISORY] SQUID-2026:1 Denial of Service in ICP Request handling (CVE-2026-33526)

http://www.openwall.com/lists/oss-security/2026/03/25/2
github Patch Available

SQUID-2026:1 Denial of Service in ICP Request handling · Advisory · squid-cache/squid · GitHub

https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg
github_commit

commit 8a7d42f9d44b (squid-cache/squid)

Fix landed in squid-cache/squid commit 8a7d42f9d44b — awaiting tagged release

https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91

Vendor Advisories for CVE-2026-33526(11)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(12)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatsquid:4-8060020260518090356.ad008a3a2026-05-26redhat
redhatsquid:4-8040020260514123440.522a0ee42026-05-26redhat
redhatsquid:4-8080020260514105733.63b345852026-05-26redhat
redhatsquid-7:6.10-5.el10_0.22026-04-29redhat
redhatsquid-7:5.5-13.el9_4.52026-04-24redhat
redhatsquid-7:5.2-1.el9_0.102026-04-23redhat
redhatsquid-7:5.5-5.el9_2.112026-04-23redhat
redhatsquid-7:5.5-19.el9_6.32026-04-21redhat
redhatsquid-7:3.5.20-17.el7_9.162026-04-20redhat
redhatsquid:4-8100020260408092701.489197e62026-04-15redhat
redhatsquid-7:6.10-6.el10_1.32026-04-14redhat
redhatsquid-7:5.5-22.el9_7.42026-03-31redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
squid4.13-10 ... 4.13-10+deb11u6 (7 versions)4.13-10+deb11u7—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
squid5.7-2 ... 5.7-2+deb12u5 (6 versions)5.7-2+deb12u6—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
squid6.13-2, 6.13-2+deb13u16.13-2+deb13u2—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
squid6.13-2, 7.1-1, 7.2-1, 7.2-2, 7.4-17.5-1—

Weakness Classification(3)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(3)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 8× in last 7d / 32× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 113 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:30 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-15 03:11 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-12 15:01 UTCEPSS rescore
  9. 2026-09-11 14:53 UTCEPSS rescore
  10. 2026-09-11 09:37 UTCEPSS rescore
  11. 2026-09-10 09:34 UTCEPSS rescore
  12. 2026-09-08 22:00 UTCEPSS rescore
  13. 2026-09-07 16:01 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-04 05:06 UTCEPSS rescore
  17. 2026-09-02 14:11 UTCEPSS rescore
  18. 2026-09-02 14:01 UTCOSV refresh
  19. 2026-09-01 13:53 UTCEPSS rescore
  20. 2026-09-01 04:39 UTCEPSS rescore
  21. 2026-09-01 04:39 UTCEPSS rescore
  22. 2026-08-30 19:17 UTCEPSS rescore
  23. 2026-08-30 01:22 UTCEPSS rescore
  24. 2026-08-28 21:41 UTCEPSS rescore
  25. 2026-08-27 14:25 UTCEPSS rescore
Show 75 more
  1. 2026-08-26 14:46 UTCEPSS rescore
  2. 2026-08-25 13:49 UTCEPSS rescore
  3. 2026-08-24 14:17 UTCEPSS rescore
  4. 2026-08-23 00:19 UTCEPSS rescore
  5. 2026-08-21 23:49 UTCEPSS rescore
  6. 2026-08-20 22:55 UTCEPSS rescore
  7. 2026-08-20 22:55 UTCEPSS rescore
  8. 2026-08-19 17:03 UTCEPSS rescore
  9. 2026-08-18 13:48 UTCEPSS rescore
  10. 2026-08-17 13:47 UTCEPSS rescore
  11. 2026-08-16 14:56 UTCEPSS rescore
  12. 2026-08-16 10:12 UTCEG score recompute
  13. 2026-08-16 10:12 UTCVendor advisory
  14. 2026-08-16 02:14 UTCEPSS rescore
  15. 2026-08-15 01:30 UTCEPSS rescore
  16. 2026-08-14 19:28 UTCVendor advisory
  17. 2026-08-14 06:29 UTCEG score recompute
  18. 2026-08-14 06:29 UTCVendor advisory
  19. 2026-08-13 22:00 UTCEPSS rescore
  20. 2026-08-12 20:46 UTCEG score recompute
  21. 2026-08-12 20:46 UTCVendor advisory
  22. 2026-08-12 13:50 UTCEPSS rescore
  23. 2026-08-11 20:52 UTCEG score recompute
  24. 2026-08-11 20:52 UTCVendor advisory
  25. 2026-08-11 03:54 UTCVendor advisory
  26. 2026-08-10 05:39 UTCVendor advisory
  27. 2026-08-09 17:50 UTCEG score recompute
  28. 2026-08-09 17:50 UTCVendor advisory
  29. 2026-08-09 13:46 UTCEPSS rescore
  30. 2026-08-09 06:02 UTCEG score recompute
  31. 2026-08-09 06:02 UTCVendor advisory
  32. 2026-08-08 16:37 UTCEPSS rescore
  33. 2026-08-08 04:14 UTCEG score recompute
  34. 2026-08-08 04:14 UTCVendor advisory
  35. 2026-08-07 16:26 UTCVendor advisory
  36. 2026-08-06 18:49 UTCEG score recompute
  37. 2026-08-06 18:49 UTCVendor advisory
  38. 2026-08-06 13:46 UTCEPSS rescore
  39. 2026-08-06 00:55 UTCEG score recompute
  40. 2026-08-06 00:55 UTCVendor advisory
  41. 2026-08-05 19:17 UTCEPSS rescore
  42. 2026-08-04 15:10 UTCEPSS rescore
  43. 2026-08-04 10:38 UTCEPSS rescore
  44. 2026-08-03 23:38 UTCEG score recompute
  45. 2026-08-03 23:38 UTCVendor advisory
  46. 2026-08-03 10:36 UTCEPSS rescore
  47. 2026-08-02 15:26 UTCEG score recompute
  48. 2026-08-02 15:26 UTCVendor advisory
  49. 2026-08-02 02:27 UTCEPSS rescore
  50. 2026-08-01 04:16 UTCEPSS rescore
  51. 2026-07-30 16:28 UTCEPSS rescore
  52. 2026-07-30 01:30 UTCEPSS rescore
  53. 2026-07-27 14:13 UTCEPSS rescore
  54. 2026-07-25 14:18 UTCEPSS rescore
  55. 2026-07-25 14:18 UTCEPSS rescore
  56. 2026-07-24 14:17 UTCEPSS rescore
  57. 2026-07-24 14:17 UTCEPSS rescore
  58. 2026-07-23 14:18 UTCEPSS rescore
  59. 2026-07-23 14:18 UTCEPSS rescore
  60. 2026-07-23 03:09 UTCEG score recompute
  61. 2026-07-22 14:08 UTCEPSS rescore
  62. 2026-07-21 15:24 UTCEPSS rescore
  63. 2026-07-20 17:08 UTCEPSS rescore
  64. 2026-07-19 14:31 UTCEPSS rescore
  65. 2026-07-19 02:29 UTCEPSS rescore
  66. 2026-07-18 10:04 UTCEPSS rescore
  67. 2026-07-18 06:59 UTCOSV refresh
  68. 2026-07-16 17:03 UTCEPSS rescore
  69. 2026-07-15 16:57 UTCEPSS rescore
  70. 2026-07-15 16:57 UTCEPSS rescore
  71. 2026-07-15 02:00 UTCEPSS rescore
  72. 2026-07-13 22:30 UTCEPSS rescore
  73. 2026-07-13 06:13 UTCEPSS rescore
  74. 2026-07-13 06:13 UTCEPSS rescore
  75. 2026-07-12 05:46 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-33526?
CVE-2026-33526 is a high vulnerability published on March 26, 2026. 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…
When was CVE-2026-33526 disclosed?
CVE-2026-33526 was first published in the National Vulnerability Database on March 26, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33526 actively exploited?
CVE-2026-33526 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 9% probability of exploitation in the next 30 days, which ranks it in the top 5.0% of all scored CVEs.
What is the CVSS score of CVE-2026-33526?
CVE-2026-33526 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-33526?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33526, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-33526

Explore →

Is Your Infrastructure Affected by CVE-2026-33526?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs