GHSL-2026-118: 7-Zip UDF Field OOB Read
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mcmilk | 7-Zip | affected |
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No data.
| Vendor | Product | Versions | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Mcmilk | 7-zip |
|
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4681-1 | p7zip security update |
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.189% probability within 30 days)
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
7-zip
7-zip 7-zip |
|
| CPEs | cpe:2.3:a:7-zip:7-zip:*:*:*:*:*:*:*:* | |
| Vendors & Products |
7-zip
7-zip 7-zip |
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Mcmilk
Mcmilk 7-zip |
|
| Vendors & Products |
Mcmilk
Mcmilk 7-zip |
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 7-Zip is a file archiver with a high compression ratio. Versions 9.11 through 26.00 contain a heap out-of-bounds read of up to 3 bytes in the UDF disc image handler's File Identifier Descriptor parser. In CFileId::Parse (CPP/7zip/Archive/Udf/UdfIn.cpp), after validating size < 38 + idLen + impLen and advancing processed to 38 + impLen + idLen, the alignment-padding loop reads p[processed] while incrementing up to 3 times to reach a 4-byte boundary, and the processed <= size bounds check only runs after the loop. When (38 + impLen + idLen) % 4 != 0 and 38 + impLen + idLen == size, the loop reads 1 to 3 bytes past the end of the exact-size heap buffer allocated via buf.Alloc((size_t)item.Size). The UDF handler is registered for .iso and .udf files and auto-detected by signature, and the OOB read triggers during Open() when listing or extracting a crafted UDF image. Impact is limited to information disclosure (a 1-bit oracle per OOB byte via open/fail behavior) and denial of service (crash under hardened allocators); there is no write primitive. Version 26.01 fixes the issue. | |
| Title | GHSL-2026-118: 7-Zip UDF Field OOB Read | |
| Weaknesses | CWE-125 | |
| References |
| |
| Metrics |
cvssV3_1
|