This is an automated email from the ASF dual-hosted git repository. pkarwasz pushed a commit to branch fix/new-cves in repository https://gitbox.apache.org/repos/asf/logging-site.git
commit 83df9f132024f1e5a4aa0235ad8359d63002370c Author: Piotr P. Karwasz <[email protected]> AuthorDate: Fri Apr 10 14:44:27 2026 +0200 Add details for CVE-2026-34480 --- .../modules/ROOT/pages/_vulnerabilities.adoc | 42 ++++++++++++++ src/site/static/cyclonedx/vdr.xml | 65 ++++++++++++++++++++++ 2 files changed, 107 insertions(+) diff --git a/src/site/antora/modules/ROOT/pages/_vulnerabilities.adoc b/src/site/antora/modules/ROOT/pages/_vulnerabilities.adoc index 3fc9896c..d81d5694 100644 --- a/src/site/antora/modules/ROOT/pages/_vulnerabilities.adoc +++ b/src/site/antora/modules/ROOT/pages/_vulnerabilities.adoc @@ -29,6 +29,48 @@ Version ranges follow the https://github.com/package-url/vers-spec/blob/main/VER For brevity, mathematical interval notation is used, with the union operator (`∪`) to represent multiple ranges. ==== +[#CVE-2026-34480] +== {cve-url-prefix}/CVE-2026-34480[CVE-2026-34480] + +[cols="1h,5"] +|=== +|Summary |Silent log event loss in `XmlLayout` due to unescaped XML 1.0 forbidden characters +|CVSS 4.x Score & Vector |6.9 MEDIUM (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N) +|Components affected |Log4j Core +|Versions affected |`[2.0-alpha1, 2.25.4) ∪ [3.0.0-alpha1, 3.0.0-beta3]` +|Versions fixed |`2.25.4` +|=== + +[#CVE-2026-34480-description] +=== Description + +Apache Log4j Core's +https://logging.apache.org/log4j/2.x/manual/layouts.html#XmlLayout[`XmlLayout`], +in versions up to and including 2.25.3, fails to sanitize characters forbidden by the +https://www.w3.org/TR/xml/#charsets[XML 1.0 specification] +producing invalid XML output whenever a log message or MDC value contains such characters. + +The impact depends on the StAX implementation in use: + +* *JRE built-in StAX:* Forbidden characters are silently written to the output, producing malformed XML. +Conforming parsers must reject such documents with a fatal error, which may cause downstream log-processing systems to drop the affected records. +* *Alternative StAX implementations* (e.g., https://github.com/FasterXML/woodstox[Woodstox], a transitive dependency of the Jackson XML Dataformat module): An exception is thrown during the logging call, and the log event is never delivered to its intended appender, only to Log4j's internal status logger. + +[#CVE-2026-34480-remediation] +=== Remediation + +Users are advised to upgrade to Apache Log4j Core version `2.25.4`, which corrects this issue by sanitizing forbidden characters before XML output. + +[#CVE-2026-34480-credits] +=== Credits + +This issue was originally reported by Ap4sh (Samy Medjahed) and Ethicxz (Eliott Laurie), and independently reported by jabaltarik1. + +[#CVE-2026-34480-references] +=== References +* {cve-url-prefix}/CVE-2026-34480[CVE-2026-34480] +* https://github.com/apache/logging-log4j2/pull/4077[Pull request that fixes the issue] + [#CVE-2026-34479] == {cve-url-prefix}/CVE-2026-34479[CVE-2026-34479] diff --git a/src/site/static/cyclonedx/vdr.xml b/src/site/static/cyclonedx/vdr.xml index c1e60f78..96f94f98 100644 --- a/src/site/static/cyclonedx/vdr.xml +++ b/src/site/static/cyclonedx/vdr.xml @@ -89,6 +89,71 @@ <vulnerabilities> + <vulnerability> + <id>CVE-2026-34480</id> + <source> + <name>NVD</name> + <url>https://nvd.nist.gov/vuln/detail/CVE-2026-34480</url> + </source> + <ratings> + <rating> + <source> + <name>The Apache Software Foundation</name> + <url> + <![CDATA[https://www.first.org/cvss/calculator/4-0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N]]></url> + </source> + <score>6.9</score> + <severity>medium</severity> + <method>CVSSv4</method> + <vector>AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N</vector> + </rating> + </ratings> + <cwes> + <cwe>116</cwe> + </cwes> + <description><![CDATA[Apache Log4j Core's +https://logging.apache.org/log4j/2.x/manual/layouts.html#XmlLayout[`XmlLayout`], +in versions up to and including 2.25.3, fails to sanitize characters forbidden by the +https://www.w3.org/TR/xml/#charsets[XML 1.0 specification] +producing invalid XML output whenever a log message or MDC value contains such characters. + +The impact depends on the StAX implementation in use: + +* *JRE built-in StAX:* Forbidden characters are silently written to the output, producing malformed XML. +Conforming parsers must reject such documents with a fatal error, which may cause downstream log-processing systems to drop the affected records. +* *Alternative StAX implementations* (e.g., https://github.com/FasterXML/woodstox[Woodstox], a transitive dependency of the Jackson XML Dataformat module): An exception is thrown during the logging call, and the log event is never delivered to its intended appender, only to Log4j's internal status logger.]]></description> + <recommendation><![CDATA[Users are advised to upgrade to Apache Log4j Core version `2.25.4`, which corrects this issue by sanitizing forbidden characters before XML output.]]></recommendation> + <created>2026-04-10T11:53:17Z</created> + <published>2026-04-10T11:53:17Z</published> + <updated>2026-04-10T11:53:17Z</updated> + <credits> + <individuals> + <individual> + <name>Ap4sh (Samy Medjahed)</name> + </individual> + <individual> + <name>Ethicxz (Eliott Laurie)</name> + </individual> + <individual> + <name>jabaltarik1</name> + </individual> + </individuals> + </credits> + <affects> + <target> + <ref>log4j-core</ref> + <versions> + <version> + <range><![CDATA[vers:maven/>=2.0-alpha1|<2.25.4]]></range> + </version> + <version> + <range><![CDATA[vers:maven/>=3.0.0-alpha1|<=3.0.0-beta3]]></range> + </version> + </versions> + </target> + </affects> + </vulnerability> + <vulnerability> <id>CVE-2026-34479</id> <source>
