{"answers":{"affected":"2 open source packages ship an affected version, including AjaxNetProfessional. It affects 2 products.","exploited":"Yes. Attackers have exploited CVE-2021-23758 in the wild since at least 26 Aug 2026.","fix":"Upgrade AjaxNetProfessional to 21.11.29.1 or later. US federal agencies must fix it by 9 Sep 2026.","what":"CVE-2021-23758 is a high-severity unsafe deserialization vulnerability in AjaxPro.2, published on 3 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-23758 and fix it if it is affected.\n\nWhat it is: CVE-2021-23758 is a high-severity unsafe deserialization vulnerability in AjaxPro.2, published on 3 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: Yes. Attackers have exploited CVE-2021-23758 in the wild since at least 26 Aug 2026.\n\nAffected packages and fixed versions:\n- AjaxNetProfessional (NuGet): affected all versions; fixed in 21.11.29.1\n- AjaxNetProfessional (NuGet): affected all versions; fixed in 21.11.29.1\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-2021-23758/ (Markdown: https://insights.sbomify.com/CVE-2021-23758/index.md)","id":"CVE-2021-23758","markdown":"https://insights.sbomify.com/CVE-2021-23758/index.md","name":"CVE-2021-23758","record":{"aliases":["GHSA-6r7c-6w96-8pvw","SNYK-DOTNET-AJAXPRO2-1925971"],"analysis":{"component_type":"library","fix_type":"no_fix_stated","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"AjaxPro.2 .NET library","requires_auth":"none","summary":"Attackers can achieve remote code execution by exploiting unsafe deserialization of arbitrary .NET classes in the AjaxPro.2 library.","user_interaction":"not_required","vuln_class":"deserialization"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"snyk","cpe":[{"product":"ajaxpro.2","vendor":"ajaxpro.2_project"},{"product":"ajax.net_professional","vendor":"michaelschwarz"}],"cvss":{"score":8.1,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-502","name":"Deserialization of Untrusted Data"}],"description":"All versions of package ajaxpro.2 are vulnerable to Deserialization of Untrusted Data due to the possibility of deserialization of arbitrary .NET classes, which can be abused to gain remote code execution.","ecosystems":["NuGet"],"exploits":{"exploitdb":0,"first_seen":"2021-12-03","github_poc":1,"max_poc_stars":18,"metasploit":1,"nuclei":0,"refs":[{"date":"2021-12-15T15:40:45Z","kind":"github_poc","ref":"https://github.com/numanturle/CVE-2021-23758-POC","stars":18,"title":null},{"date":"2021-12-03","kind":"metasploit","ref":"exploit/windows/http/ajaxpro_deserialization_rce","stars":null,"title":"AjaxPro Deserialization Remote Code Execution"}],"tier":"exploited"},"has_fix":true,"headline":"Ajax.NET Professional Deserialization of Untrusted Data","id":"CVE-2021-23758","indexable":true,"kev":{"dateAdded":"2026-08-26","dueDate":"2026-09-09","knownRansomwareCampaignUse":"Unknown","product":"Ajax.NET Professional","requiredAction":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","vendorProject":"Ajax.NET Professional","vulnerabilityName":"Ajax.NET Professional Deserialization of Untrusted Data Vulnerability"},"kind":"cve","links":{"ecosystem":"NuGet","product":null,"products":[],"type":"deserialization","year":"2021"},"n_packages":2,"n_references":3,"next":{"headline":"Prototype Pollution","id":"CVE-2021-23760"},"packages":[{"ecosystem":"NuGet","fixed":["21.11.29.1"],"introduced":["0"],"last_affected":[],"package":"AjaxNetProfessional","purl":null,"source":"GHSA-6r7c-6w96-8pvw"},{"ecosystem":"NuGet","fixed":["21.11.29.1"],"introduced":["0"],"last_affected":[],"package":"AjaxNetProfessional","purl":"pkg:nuget/AjaxNetProfessional","source":"GHSA-6r7c-6w96-8pvw"}],"prev":{"headline":"Arbitrary Code Execution","id":"CVE-2021-23732"},"products":["AjaxPro.2"],"published":"2021-12-03","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":"US public information, NVD API terms","name":"NVD"},{"class":"open","licence":"CC0 1.0","name":"CISA KEV"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"},{"class":"attribution","licence":"BSD-3-Clause","name":"Metasploit"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":"no","exploitation":"active","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-08-27","vendors":["n/a"]},"summary":"Attackers can achieve remote code execution by exploiting unsafe deserialization of arbitrary .NET classes in the AjaxPro.2 library.","url":"https://insights.sbomify.com/CVE-2021-23758/"}