CVE-2026-40492 (GCVE-0-2026-40492)
Vulnerability from cvelistv5 – Published: 2026-04-18 01:39 – Updated: 2026-04-18 01:39
VLAI?
Title
SAIL has heap buffer overflow in XWD decoder — bits_per_pixel vs pixmap_depth type confusion in byte-swap
Summary
SAIL is a cross-platform library for loading and saving images with support for animation, metadata, and ICC profiles. Prior to commit 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02, the XWD codec resolves pixel format based on `pixmap_depth` but the byte-swap code uses `bits_per_pixel` independently. When `pixmap_depth=8` (BPP8_INDEXED, 1 byte/pixel buffer) but `bits_per_pixel=32`, the byte-swap loop accesses memory as `uint32_t*`, reading/writing 4x the allocated buffer size. This is a different vulnerability from the previously reported GHSA-3g38-x2pj-mv55 (CVE-2026-27168), which addressed `bytes_per_line` validation. Commit 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02 contains a patch.
Severity ?
9.8 (Critical)
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| HappySeaFox | sail |
Affected:
< 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02
|
{
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"affected": [
{
"product": "sail",
"vendor": "HappySeaFox",
"versions": [
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"status": "affected",
"version": "\u003c 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02"
}
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}
],
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"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
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"problemTypes": [
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"description": "CWE-787: Out-of-bounds Write",
"lang": "en",
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"providerMetadata": {
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"shortName": "GitHub_M"
},
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"tags": [
"x_refsource_CONFIRM"
],
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},
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}
],
"source": {
"advisory": "GHSA-526v-vm72-4v64",
"discovery": "UNKNOWN"
},
"title": "SAIL has heap buffer overflow in XWD decoder \u2014 bits_per_pixel vs pixmap_depth type confusion in byte-swap"
}
},
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"dateReserved": "2026-04-13T19:50:42.115Z",
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}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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