CVE-2018-1285 — Apache log4net versions before 2

Apache log4net versions before 2.0.10 do not disable XML external entities when parsing log4net configuration files. This allows for XXE-based attacks in applications that accept attacker-controlled log4net configuration files.

01What is this vulnerability?

Apache log4net versions before 2.0.10 do not disable XML external entities when parsing log4net configuration files. This allows for XXE-based attacks in applications that accept attacker-controlled log4net configuration files.

02Affected products

Vendor	Product	Versions
n	a / Apache log4net	Apache log4net up to 2.0.8

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2020-05-11T16:41:28.000Z
• Last modified: 2024-08-05T03:59:37.654Z

09References

• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.apache.org — https://lists.apache.org/thread.html/r33564de316d4e4ba0fea1d4d079e62cde1ffe64369…
• lists.apache.org — https://lists.apache.org/thread.html/r9de86a185575e6c5f92e2a70a1d2e2e9514dc43412…
• lists.apache.org — https://lists.apache.org/thread.html/r6543acafca3e2d24ff4b0c364a91540cb9378977ff…
• lists.apache.org — https://lists.apache.org/thread.html/r7ab6b6e702f11a6f77b0db2af2d5e5532f56ae4b99…
• lists.apache.org — https://lists.apache.org/thread.html/rdbac24c945ca5c69cd5348b5ac023bc625768f6533…
• lists.apache.org — https://lists.apache.org/thread.html/rd2d72a017e238d1f345f9d14e075c81be16fc68a41…
• lists.apache.org — https://lists.apache.org/thread.html/r00b16ac5e0bbf7009a0d167ed58f3f94d0033b0f4b…
• www.oracle.com — https://www.oracle.com/security-alerts/cpujan2021.html
• lists.apache.org — https://lists.apache.org/thread.html/reab1c277c95310bad1038255e0757857b2fbe29141…
• issues.apache.org — https://issues.apache.org/jira/browse/LOG4NET-575
• www.oracle.com — https://www.oracle.com/security-alerts/cpuApr2021.html
• lists.apache.org — https://lists.apache.org/thread.html/r525cbbd7db0aef4a114cf60de8439aa285decc3490…
• www.oracle.com — https://www.oracle.com/security-alerts/cpuapr2022.html
• security.netapp.com — https://security.netapp.com/advisory/ntap-20220909-0001/