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
Elevated
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 13%CVSS: 7.5Exploit: Elevated riskExposed services: Not assessed

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
7.5HIGHmedium confidence
EG Risk
52
EG Risk 52/100

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%
EPSS PROB
13%
EPSS %ILE
96th
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.
redhatMentions a patch (unverified)

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
redhatMentions a patch (unverified)

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
redhatMentions a patch (unverified)

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
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 10.0 Extended Update Support.

https://access.redhat.com/errata/RHSA-2026:11901
redhatMentions a patch (unverified)

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

https://access.redhat.com/errata/RHSA-2026:10257
redhatMentions a patch (unverified)

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

https://access.redhat.com/errata/RHSA-2026:10256
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 9.4 Extended Update Support.

https://access.redhat.com/errata/RHSA-2026:10255
genericMentions a patch (unverified)

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
githubMentions a patch (unverified)

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(13)

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 / EcosystemFix (by version range) / 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 rangeFix by version rangeDependents
squid4.13-10 ... 4.13-10+deb11u6 (7 versions)
  • every version up to 4.13-10+deb11u7: fixed in 4.13-10+deb11u7
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
squid5.7-2 ... 5.7-2+deb12u5 (6 versions)
  • every version up to 5.7-2+deb12u6: fixed in 5.7-2+deb12u6
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
squid6.13-2, 6.13-2+deb13u1
  • every version up to 6.13-2+deb13u2: fixed in 6.13-2+deb13u2
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
squid6.13-2, 7.1-1, 7.2-1, 7.2-2, 7.4-1
  • every version up to 7.5-1: fixed in 7.5-1
—

Weakness Classification(3)

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

Additional Vendor Advisories

(1)

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 6× in last 7d / 23× 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 126 total refreshes for this CVE.

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

Related CVEs(same product + same vendor + same CWE)

Same vendor

2 shown

redhat:RHSA-2026:10255 · ubuntu:USN-8157-1

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 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 13% probability of exploitation in the next 30 days (96th percentile of EPSS-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?
A fix for CVE-2026-33526 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-33526 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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