# CVE-2026-53938: OpenIDC/cjose has a heap buffer overflow in AES Key Wrap decryption (A128KW/A192KW/A256KW) > A remote attacker can trigger a heap buffer overflow in the cjose library via crafted JWE messages, causing crashes or potential code execution. - **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 8 Sep 2026 - **Updated:** 9 Sep 2026 - **Also known as:** ALSA-2026:79122, ALSA-2026:90812, AZL-101093, DEBIAN-CVE-2026-53938, GHSA-75r7-f5cv-g3wj, RHSA-2026:73017, RHSA-2026:73018, RHSA-2026:73128, RHSA-2026:73129, RHSA-2026:77370, RHSA-2026:77371, RHSA-2026:77372, RHSA-2026:79122, RLSA-2026:79122, UBUNTU-CVE-2026-53938 ## What is CVE-2026-53938? CVE-2026-53938 is a high-severity memory corruption vulnerability in OpenIDC cjose, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). Prior to version 0.6.2.5, cjose's JWE decryption path for the AES Key Wrap key-management algorithms (`alg` = `A128KW`, `A192KW`, `A256KW`) does not validate the length of the attacker-supplied `encrypted_key` (JWE Encrypted Key) before unwrapping it into a fixed-size, heap-allocated Content Encryption Key (CEK) buffer. A remote, unauthenticated attacker who can submit a crafted JWE to an application that decrypts it with an AES-KW symmetric key can trigger an out-of-bounds heap write, corrupting the heap. This leads at minimum to a crash (denial of service) and, depending on the heap layout and allocator, may be leverageable for further memory-corruption impact. `cjose_jwe_import()` / `cjose_jwe_decrypt()` are pre-authentication entry points: they parse and process fully attacker-controlled input. Upgrade to cjose 0.6.2.5 to receive a patch. If upgrading is not immediately possible, reject the AES Key Wrap algorithms (`A128KW`/`A192KW`/`A256KW`) for untrusted JWEs at the application layer. Weakness: CWE-787 (Out-of-bounds Write), CWE-122 (Heap-based Buffer Overflow) ## Which versions are affected by CVE-2026-53938? | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `cjose` | AlmaLinux:10 | All versions | 0.6.2.2-7.el10_2.1 | | `cjose-devel` | AlmaLinux:10 | All versions | 0.6.2.2-7.el10_2.1 | | `cjose` | AlmaLinux:9 | All versions | 0.6.1-17.el9_8.1 | | `cjose-devel` | AlmaLinux:9 | All versions | 0.6.1-17.el9_8.1 | | `cjose` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.6.2.2-7.el10_2.1 | | `cjose-debuginfo` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.6.2.2-7.el10_2.1 | | `cjose-debugsource` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.6.2.2-7.el10_2.1 | | `cjose-devel` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.6.2.2-7.el10_2.1 | | `cjose` | Red Hat:enterprise_linux_eus:10.0 | All versions | 0:0.6.2.2-7.el10_0.1 | | `cjose-debuginfo` | Red Hat:enterprise_linux_eus:10.0 | All versions | 0:0.6.2.2-7.el10_0.1 | | `cjose-debugsource` | Red Hat:enterprise_linux_eus:10.0 | All versions | 0:0.6.2.2-7.el10_0.1 | | `cjose-devel` | Red Hat:enterprise_linux_eus:10.0 | All versions | 0:0.6.2.2-7.el10_0.1 | | `cjose` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:0.6.1-3.module+el8.4.0+24972+63eee48e.1 | | `cjose-debuginfo` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:0.6.1-3.module+el8.4.0+24972+63eee48e.1 | | `cjose-debugsource` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:0.6.1-3.module+el8.4.0+24972+63eee48e.1 | | `cjose-devel` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:0.6.1-3.module+el8.4.0+24972+63eee48e.1 | | `mod_auth_openidc` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.4.9.4-1.module+el8.4.0+24868+593d10ef.3 | | `mod_auth_openidc-debuginfo` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.4.9.4-1.module+el8.4.0+24868+593d10ef.3 | | `mod_auth_openidc-debugsource` | Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.4.9.4-1.module+el8.4.0+24868+593d10ef.3 | | `cjose` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:0.6.1-3.module+el8.6.0+24971+334c209b.1 | | `cjose-debuginfo` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:0.6.1-3.module+el8.6.0+24971+334c209b.1 | | `cjose-debugsource` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:0.6.1-3.module+el8.6.0+24971+334c209b.1 | | `cjose-devel` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:0.6.1-3.module+el8.6.0+24971+334c209b.1 | | `mod_auth_openidc` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:2.4.9.4-1.module+el8.6.0+24867+df0294a5.3 | | `mod_auth_openidc-debuginfo` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:2.4.9.4-1.module+el8.6.0+24867+df0294a5.3 | | `mod_auth_openidc-debugsource` | Red Hat:rhel_aus:8.6::appstream | All versions | 0:2.4.9.4-1.module+el8.6.0+24867+df0294a5.3 | | `cjose` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:0.6.1-3.module+el8.8.0+24970+620d53ef.1 | | `cjose-debuginfo` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:0.6.1-3.module+el8.8.0+24970+620d53ef.1 | | `cjose-debugsource` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:0.6.1-3.module+el8.8.0+24970+620d53ef.1 | | `cjose-devel` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:0.6.1-3.module+el8.8.0+24970+620d53ef.1 | | `mod_auth_openidc` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:2.4.9.4-1.module+el8.8.0+24885+7d8e9f68.3 | | `mod_auth_openidc-debuginfo` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:2.4.9.4-1.module+el8.8.0+24885+7d8e9f68.3 | | `mod_auth_openidc-debugsource` | Red Hat:rhel_e4s:8.8::appstream | All versions | 0:2.4.9.4-1.module+el8.8.0+24885+7d8e9f68.3 | | `cjose` | Red Hat:rhel_e4s:9.2::appstream | All versions | 0:0.6.1-13.el9_2.1 | | `cjose-debuginfo` | Red Hat:rhel_e4s:9.2::appstream | All versions | 0:0.6.1-13.el9_2.1 | | `cjose-debugsource` | Red Hat:rhel_e4s:9.2::appstream | All versions | 0:0.6.1-13.el9_2.1 | | `cjose` | Red Hat:rhel_e4s:9.4::appstream | All versions | 0:0.6.1-16.el9_4.1 | | `cjose-debuginfo` | Red Hat:rhel_e4s:9.4::appstream | All versions | 0:0.6.1-16.el9_4.1 | | `cjose-debugsource` | Red Hat:rhel_e4s:9.4::appstream | All versions | 0:0.6.1-16.el9_4.1 | | `cjose` | Red Hat:rhel_eus:9.6::appstream | All versions | 0:0.6.1-17.el9_6.1 | ## How do I fix CVE-2026-53938? Upgrade to a fixed version. ## Is CVE-2026-53938 being exploited? There is no known exploitation of CVE-2026-53938 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-53938 and fix it if it is affected. What it is: CVE-2026-53938 is a high-severity memory corruption vulnerability in OpenIDC cjose, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-53938 in the wild and no public exploit code. Affected product: OpenIDC cjose. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. 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. 2. 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. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-53938/ (Markdown: https://insights.sbomify.com/CVE-2026-53938/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53938 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53938 - OSV: https://osv.dev/vulnerability/CVE-2026-53938 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-53938/ Summaries are generated and may contain mistakes; the official description above is the record.