[UPDATE] [medium] Apache log4j: Multiple vulnerabilities allow file manipulation

mediumCVE-2026-34477 CVE-2026-34478 CVE-2026-34479 CVE-2026-34480 CVE-2026-34481

An attacker can exploit multiple vulnerabilities in Apache log4j to manipulate files.

CSIRTS triage

vendor: Apache product: log4jOther

What: An attacker can exploit multiple vulnerabilities in Apache log4j to manipulate files.
Who is affected: Deployments using Apache log4j.
Urgency: Remediation is medium urgency as the vulnerabilities could lead to file manipulation.
Action: Apply patches as they become available.

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

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-07-10
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-1067

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-2026-344770.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all scored CVEs.
Low exploitation riskCVE-2026-344780.83% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 53% of all scored CVEs.
Low exploitation riskCVE-2026-344790.53% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 41% of all scored CVEs.
Low exploitation riskCVE-2026-344800.86% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 54% of all scored CVEs.
Low exploitation riskCVE-2026-344810.56% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 42% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-34477	coverage & exploitation status	NVD · CVE.org
CVE-2026-34478	coverage & exploitation status	NVD · CVE.org
CVE-2026-34479	coverage & exploitation status	NVD · CVE.org
CVE-2026-34480	coverage & exploitation status	NVD · CVE.org
CVE-2026-34481	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

high[NEW] [high] IBM Operational Decision Manager: Multiple vulnerabilitiescert-bund
unknownMultiple vulnerabilities in IBM products (June 26, 2026)cert-fr-avis
unknownNCSC-2026-0202 [1.00] [M/H] Vulnerabilities fixed in Oracle Enterprise Managerncsc-nl
unknownNCSC-2026-0200 [1.00] [M/H] Vulnerabilities fixed in Oracle Communicationsncsc-nl

Recent advisories for Apache log4j

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

unknownCVE-2026-49844: Improper encoding of non-finite floating-point values during MapMessage JSON serialization in …nvd · 2026-07-10
critical[UPDATE] [critical] Apache log4j: Vulnerability allows code executioncert-bund · 2026-07-08