CVE-2026-33857: Apache HTTP Server: Off-by-one OOB reads in AJP getter functions

mediumCVSS 5.3CVE-2026-33857

CSIRTS triage

vendor: Apache product: HTTP Server Information disclosure Memory corruption

What: AJP getter functions in Apache HTTP Server contain off-by-one out-of-bounds read vulnerabilities.
Who is affected: Apache HTTP Server instances using AJP connector are affected.
Urgency: Medium severity (CVSS 5.3); out-of-bounds reads may leak memory contents.
Action: Update Apache HTTP Server to patch the off-by-one errors in AJP getter functions.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.3
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33857

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-338570.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-33857	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

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