{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-77803 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-77803 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-77803 is a low-severity vulnerability in Progress® Telerik® Fiddler® Classic, published on 5 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-77803 and fix it if it is affected.\n\nWhat it is: CVE-2026-77803 is a low-severity vulnerability in Progress® Telerik® Fiddler® Classic, published on 5 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-77803 in the wild and no public exploit code.\n\nAffected product: Progress® Telerik® Fiddler® Classic. 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-2026-77803/ (Markdown: https://insights.sbomify.com/CVE-2026-77803/index.md)","id":"CVE-2026-77803","markdown":"https://insights.sbomify.com/CVE-2026-77803/index.md","name":"CVE-2026-77803","record":{"aliases":["GHSA-xq67-hr2w-mm32"],"analysis":{"component_type":"desktop_application","fix_type":"upgrade","impacts":["data_read","security_bypass"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Fiddler Classic proxy","requires_auth":"low_privilege","summary":"A local attacker can exploit HTTP request desynchronization in Fiddler Classic to split requests and smuggle responses, bypassing security controls.","user_interaction":"not_required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"ProgressSoftware","cpe":[],"cvss":{"score":3.6,"severity":"low","source":"cna","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-444","name":"Inconsistent Interpretation of HTTP Requests"}],"description":"In Progress® Telerik® Fiddler® Classic for Windows, versions prior to v6.0.20262.10021, front-end request desynchronization is possible in the proxy request forwarding component. A request that contains both a Content-Length and a Transfer-Encoding header is forwarded with both headers present, while Fiddler frames the body using Transfer-Encoding only. The remaining bytes on the reused client connection are then parsed as a separate pipelined request, so a local threat actor with low privileges can cause a single malformed request to be split into two requests forwarded to the origin server and receive an additional smuggled response, without requiring a vulnerable server.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Front-end Desynchronization Vulnerability in Progress® Telerik® Fiddler® Classic","id":"CVE-2026-77803","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"other","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"Race condition in Progress® Telerik® Fiddler® Classic","id":"CVE-2026-77804"},"packages":[],"prev":{"headline":"HTTP Request Smuggling Vulnerability in Progress® Telerik® Fiddler® Classic","id":"CVE-2026-77802"},"products":["Progress® Telerik® Fiddler® Classic"],"published":"2026-10-05","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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-06","vendors":["Progress Software"]},"summary":"A local attacker can exploit HTTP request desynchronization in Fiddler Classic to split requests and smuggle responses, bypassing security controls.","url":"https://insights.sbomify.com/CVE-2026-77803/"}