{"id":"CVE-2026-62298","aliases":["EUVD-2026-114330","GHSA-rcj5-gcvg-x796"],"status":"published","title":"asn1c: ASAN crash with decode of open types","description":"mouse07410/asn1c is an ASN.1 compiler. Prior to 1.2.5, `OPEN TYPE` decoding can dereference an unallocated member pointer and crash the consuming program. `OPEN_TYPE_aper_get` in `OPEN_TYPE_aper.c`, `OPEN_TYPE_ber_get` in `OPEN_TYPE_ber.c`, `OPEN_TYPE_oer_get` in `OPEN_TYPE_oer.c`, and `OPEN_TYPE_uper_get` in `OPEN_TYPE_uper.c` share the pattern: a conditional null check on `*memb_ptr2` resets presence only when the member exists, but execution then unconditionally computes an inner value from that pointer and a member offset. If the `OPEN TYPE` member has not been allocated, the null-pointer arithmetic and subsequent read cause a segmentation fault. The advisory demonstrates UPER and APER crashes for `E2connectionUpdateAcknowledge`, notes that `E2AP` uses APER, and provides a BER reproducer; OER is also explicitly identified as affected. This issue is fixed in version 1.2.5.","severity":{"version":"4.0","score":0,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N","level":"none","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00502,"percentile":0.43411,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-476"],"published":"2026-10-30T18:56:59Z","modified":"2026-11-01T07:17:57Z","products":[{"vendor":"mouse07410","product":"asn1c"}],"references":[{"url":"https://github.com/mouse07410/asn1c/security/advisories/GHSA-rcj5-gcvg-x796","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/mouse07410/asn1c/commit/3f7d3bbac8cd195d552945e79586ca5000f33280","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/mouse07410/asn1c/commit/71ae41bd1cb146a432a39f72010b48f45ad69463","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/mouse07410/asn1c/releases/tag/v1.2.5","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62298.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-62298","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-62298","title":"asn1c: ASAN crash with decode of open types","description":"mouse07410/asn1c is an ASN.1 compiler. Prior to 1.2.5, `OPEN TYPE` decoding can dereference an unallocated member pointer and crash the consuming program. `OPEN_TYPE_aper_get` in `OPEN_TYPE_aper.c`, `OPEN_TYPE_ber_get` in `OPEN_TYPE_ber.c`, `OPEN_TYPE_oer_get` in `OPEN_TYPE_oer.c`, and `OPEN_TYPE_uper_get` in `OPEN_TYPE_uper.c` share the pattern: a conditional null check on `*memb_ptr2` resets presence only when the member exists, but execution then unconditionally computes an inner value from that pointer and a member offset. If the `OPEN TYPE` member has not been allocated, the null-pointer arithmetic and subsequent read cause a segmentation fault. The advisory demonstrates UPER and APER crashes for `E2connectionUpdateAcknowledge`, notes that `E2AP` uses APER, and provides a BER reproducer; OER is also explicitly identified as affected. This issue is fixed in version 1.2.5.","status":"published","published":"2026-10-30T18:56:59.029Z","modified":"2026-10-30T22:15:29.845Z","cvss":[{"version":"4.0","score":0,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N","level":"none","assessor":"cna"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:20:14.999906Z"}],"euvd":[{"id":"EUVD-2026-114330","description":"mouse07410/asn1c is an ASN.1 compiler. Prior to 1.2.5, `OPEN TYPE` decoding can dereference an unallocated member pointer and crash the consuming program. `OPEN_TYPE_aper_get` in `OPEN_TYPE_aper.c`, `OPEN_TYPE_ber_get` in `OPEN_TYPE_ber.c`, `OPEN_TYPE_oer_get` in `OPEN_TYPE_oer.c`, and `OPEN_TYPE_uper_get` in `OPEN_TYPE_uper.c` share the pattern: a conditional null check on `*memb_ptr2` resets presence only when the member exists, but execution then unconditionally computes an inner value from that pointer and a member offset. If the `OPEN TYPE` member has not been allocated, the null-pointer arithmetic and subsequent read cause a segmentation fault. The advisory demonstrates UPER and APER crashes for `E2connectionUpdateAcknowledge`, notes that `E2AP` uses APER, and provides a BER reproducer; OER is also explicitly identified as affected. This issue is fixed in version 1.2.5.","status":"published","published":"2026-10-30T18:56:59Z","modified":"2026-10-30T22:15:29Z","updated_at":"2026-11-02T16:59:01.632804Z"}],"nvd":[{"id":"CVE-2026-62298","description":"mouse07410/asn1c is an ASN.1 compiler. Prior to 1.2.5, `OPEN TYPE` decoding can dereference an unallocated member pointer and crash the consuming program. `OPEN_TYPE_aper_get` in `OPEN_TYPE_aper.c`, `OPEN_TYPE_ber_get` in `OPEN_TYPE_ber.c`, `OPEN_TYPE_oer_get` in `OPEN_TYPE_oer.c`, and `OPEN_TYPE_uper_get` in `OPEN_TYPE_uper.c` share the pattern: a conditional null check on `*memb_ptr2` resets presence only when the member exists, but execution then unconditionally computes an inner value from that pointer and a member offset. If the `OPEN TYPE` member has not been allocated, the null-pointer arithmetic and subsequent read cause a segmentation fault. The advisory demonstrates UPER and APER crashes for `E2connectionUpdateAcknowledge`, notes that `E2AP` uses APER, and provides a BER reproducer; OER is also explicitly identified as affected. This issue is fixed in version 1.2.5.","status":"published","published":"2026-10-30T19:18:33.027Z","modified":"2026-10-30T23:17:12.577Z","cvss":[{"version":"4.0","score":0,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"none","assessor":"secondary"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:13:05.268617Z"}],"osv":[{"id":"CVE-2026-62298","title":"asn1c: ASAN crash with decode of open types","description":"mouse07410/asn1c is an ASN.1 compiler. Prior to 1.2.5, `OPEN TYPE` decoding can dereference an unallocated member pointer and crash the consuming program. `OPEN_TYPE_aper_get` in `OPEN_TYPE_aper.c`, `OPEN_TYPE_ber_get` in `OPEN_TYPE_ber.c`, `OPEN_TYPE_oer_get` in `OPEN_TYPE_oer.c`, and `OPEN_TYPE_uper_get` in `OPEN_TYPE_uper.c` share the pattern: a conditional null check on `*memb_ptr2` resets presence only when the member exists, but execution then unconditionally computes an inner value from that pointer and a member offset. If the `OPEN TYPE` member has not been allocated, the null-pointer arithmetic and subsequent read cause a segmentation fault. The advisory demonstrates UPER and APER crashes for `E2connectionUpdateAcknowledge`, notes that `E2AP` uses APER, and provides a BER reproducer; OER is also explicitly identified as affected. This issue is fixed in version 1.2.5.","status":"published","published":"2026-10-30T18:56:59.029Z","modified":"2026-11-01T07:17:57.715118845Z","cvss":[{"version":"4.0","score":0,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N","level":"none"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T15:45:13.306117Z"}]}}