Vulnerability details
CVE-2026-76077
ASN1SCC: Stack buffer overflow and out-of-bounds read in XER tokenizer NT()
Official description
ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the XER tokenizer NT() in asn1crt/asn1crt_encoding_xer.c, which is reached by all XER decode paths, copies tag characters into a fixed char Value[100] field without a length bound and reads input and lookahead bytes without checking the buffer count. A crafted XER message with an overlong tag can overwrite the tokenizer's stack frame, while a truncated tag or unterminated processing-instruction or comment sequence can read beyond the input and may cause a CPU spin. The flaws can disclose adjacent memory, corrupt stack data, crash or hang the decoder, and potentially permit code execution. This issue is fixed in version 4.7.0.1.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.1High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| esa | asn1scc | < 4.7.0.1 | CVEProject cvelistV5 (CNA) |
References and advisories
3- https://github.com/esa/asn1scc/security/advisories/GHSA-38q3-fg5h-wwf9 x_refsource_CONFIRM
- https://github.com/esa/asn1scc/commit/fe6ab763bc60d8a2def4104c15414809b45fffd9 x_refsource_MISC
- https://github.com/esa/asn1scc/releases/tag/4.7.0.1 x_refsource_MISC
Details
- Published
- 2026-11-05
- Last updated
- 2026-11-05
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
Weaknesses (CWE)
- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
- CWE-125Out-of-bounds Read
- CWE-787Out-of-bounds Write