{"answers":{"affected":"","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55556 exists.","fix":"Upgrade to a fixed version.","what":"CVE-2026-55556 is a high-severity memory corruption vulnerability in rsyslog, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-55556 and fix it if it is affected.\n\nWhat it is: CVE-2026-55556 is a high-severity memory corruption vulnerability in rsyslog, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55556 exists.\n\nAffected product: rsyslog. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-55556/ (Markdown: https://insights.sbomify.com/CVE-2026-55556/index.md)","id":"CVE-2026-55556","markdown":"https://insights.sbomify.com/CVE-2026-55556/index.md","name":"CVE-2026-55556","record":{"aliases":["AZL-104994","DEBIAN-CVE-2026-55556","ECHO-295e-562f-90a0","GHSA-947w-69ph-mc2r"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"Rsyslog logging server","requires_auth":"none","summary":"An unauthenticated remote attacker can cause a denial of service in Rsyslog by sending oversized credentials to the optional imhttp module.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":8.2,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-122","name":"Heap-based Buffer Overflow"}],"description":"Rsyslog is a rocket-fast system for log processing. From 8.2110.0 until 8.2604.0, the optional imhttp module's parse_auth_header function in contrib/imhttp/imhttp.c allocates a zero-byte heap buffer with calloc(0, len) when an HTTP Basic Authorization value exceeds its fixed work buffer, then passes that pointer to apr_base64_decode. An unauthenticated remote attacker can send an oversized encoded credential to an imhttp endpoint configured for Basic Authentication, causing decoded data to overwrite adjacent heap memory before credential validation. Deployments that do not install, load, and use imhttp with Basic Authentication are not affected. The demonstrated impact is a process crash that interrupts log collection, and code execution has not been demonstrated. This issue is fixed in version 8.2604.0.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Rsyslog: Heap buffer overflow in imhttp plugin Basic Authentication handling","id":"CVE-2026-55556","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"memory_corruption","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"browse-mcp: Arbitrary file write via unconfined download and state paths","id":"CVE-2026-55557"},"packages":[],"prev":{"headline":"Dompdf: File existence oracle via font-face stylesheet declaration","id":"CVE-2026-55555"},"products":["rsyslog"],"published":"2026-09-18","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-22","vendors":["rsyslog"]},"summary":"An unauthenticated remote attacker can cause a denial of service in Rsyslog by sending oversized credentials to the optional imhttp module.","url":"https://insights.sbomify.com/CVE-2026-55556/"}