{"answers":{"affected":"4 open source packages ship an affected version, including webpack-dev-middleware.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-76844 exists.","fix":"Upgrade webpack-dev-middleware to a fixed version for your release line: 7.4.6 or 8.3.0.","what":"CVE-2026-76844 is a high-severity memory corruption vulnerability in zlib, published on 24 Aug 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-2026-76844 and fix it if it is affected.\n\nWhat it is: CVE-2026-76844 is a high-severity memory corruption vulnerability in zlib, published on 24 Aug 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-2026-76844 exists.\n\nAffected packages and fixed versions:\n- webpack-dev-middleware (npm): affected all versions; fixed in 7.4.6\n- webpack-dev-middleware (npm): affected all versions; fixed in 7.4.6\n- webpack-dev-middleware (npm): affected from 8.0.0; fixed in 8.3.0\n- webpack-dev-middleware (npm): affected from 8.0.0; fixed in 8.3.0\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-2026-76844/ (Markdown: https://insights.sbomify.com/CVE-2026-76844/index.md)","id":"CVE-2026-76844","markdown":"https://insights.sbomify.com/CVE-2026-76844/index.md","name":"CVE-2026-76844","record":{"aliases":["AZL-105345","CLSA-2026-1787602147","CLSA-2026-1790604916","CLSA-2026-1790755864","CLSA-2026-1790756051","CLSA-2026-1790876768","CLSA-2026-1790884229","CLSA-2026-1791506807","CLSA-2026-1791666312","CLSA-2026-1791666413","CLSA-2026-1791666532","CLSA-2026-1791666638","CLSA-2026-1791677094","CLSA-2026-1791830789","CLSA-2026-1791832293","CLSA-2026-1791907762","CLSA-2026-1791907870","CLSA-2026-1791915688","CLSA-2026-1791916248","CLSA-2026-1791969403","CLSA-2026-1791970344","CLSA-2026-1791973683","CLSA-2026-1793108549","CLSA-2026-1793112587","ECHO-355f-9f1c-25e5","GHSA-g84c-rxfj-3j2c","MINI-4f5p-q8w6-j6xj","MINI-9xv9-9gj3-hfmr","MINI-f3w6-59c6-v6x5","MINI-gr24-6xrg-7m8w","MINI-q2x7-4r8x-676x","MINI-wpc4-jqx9-vx25","ROOT-APP-NPM-CVE-2026-76844"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["code_execution","denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"zlib compression library","requires_auth":"none","summary":"Heap buffer overflow in zlib allows attackers to execute arbitrary code or cause denial of service via stale pointers after write failures.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":8.3,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-787","name":"Out-of-bounds Write"}],"description":"zlib 1.2.11 through 1.3.2 contains a heap buffer overflow: after an underlying write() fails, gz_write() returns without resetting strm.next_in, leaving it pointed at the caller's buffer. A later gz* write call then derives a position from the stale pointer and writes past a heap allocation; any write() failure reaches it, including EPIPE on a blocking descriptor, and in versions before 1.3.1.2 the failed write must be followed by a gzclearerr() call.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"zlib 1.2.11 through 1.3.2 Heap Buffer Overflow via Stale gzwrite Pointer After Failed Write","id":"CVE-2026-76844","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"memory_corruption","year":"2026"},"n_packages":4,"n_references":5,"next":{"headline":"adm-zip 0.5.9 through 0.6.0 Arbitrary File Overwrite via Symlink Following on Extraction","id":"CVE-2026-76845"},"packages":[{"ecosystem":"npm","fixed":["7.4.6"],"introduced":["0"],"last_affected":[],"package":"webpack-dev-middleware","purl":null,"source":"GHSA-g84c-rxfj-3j2c"},{"ecosystem":"npm","fixed":["7.4.6"],"introduced":["0"],"last_affected":[],"package":"webpack-dev-middleware","purl":"pkg:npm/webpack-dev-middleware","source":"GHSA-g84c-rxfj-3j2c"},{"ecosystem":"npm","fixed":["8.3.0"],"introduced":["8.0.0"],"last_affected":[],"package":"webpack-dev-middleware","purl":null,"source":"GHSA-g84c-rxfj-3j2c"},{"ecosystem":"npm","fixed":["8.3.0"],"introduced":["8.0.0"],"last_affected":[],"package":"webpack-dev-middleware","purl":"pkg:npm/webpack-dev-middleware","source":"GHSA-g84c-rxfj-3j2c"}],"prev":{"headline":"Flair 0.15.0 and 0.15.1 Deserialization of Untrusted Data via ClusteringModel.load","id":"CVE-2026-76843"},"products":["zlib"],"published":"2026-08-24","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-01","vendors":["zlib"]},"summary":"Heap buffer overflow in zlib allows attackers to execute arbitrary code or cause denial of service via stale pointers after write failures.","url":"https://insights.sbomify.com/CVE-2026-76844/"}