CVE-2026-40492

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Source

https://cve.org/CVERecord?id=CVE-2026-40492

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40492.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-40492

Aliases

GHSA-526v-vm72-4v64

Downstream

DEBIAN-CVE-2026-40492

UBUNTU-CVE-2026-40492

Published

2026-04-18T01:39:48.056Z

Modified

2026-07-15T16:00:31.572086Z

Severity

9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator

Summary

SAIL has heap buffer overflow in XWD decoder — bits_per_pixel vs pixmap_depth type confusion in byte-swap

Details

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.

Database specific

{
    "cwe_ids": [
        "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40492.json",
    "cna_assigner": "GitHub_M",
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "fixed": "36aa5c7ec8a2bb35f6fb867a1177a6f141156b02"
                }
            ]
        }
    ]
}

References

Affected packages

Git / github.com/happyseafox/sail

Affected ranges

Type

GIT

Repo

https://github.com/happyseafox/sail

Events

Introduced

Fixed

36aa5c7ec8a2bb35f6fb867a1177a6f141156b02

Database specific

{
    "source": "REFERENCES"
}

Affected versions

v0.*

v0.9.0

v0.9.0-pre1

v0.9.0-pre10

v0.9.0-pre11

v0.9.0-pre12

v0.9.0-pre13

v0.9.0-pre14

v0.9.0-pre15

v0.9.0-pre16

v0.9.0-pre17

v0.9.0-pre18

v0.9.0-pre19

v0.9.0-pre2

v0.9.0-pre20

v0.9.0-pre21

v0.9.0-pre22

v0.9.0-pre23

v0.9.0-pre3

v0.9.0-pre4

v0.9.0-pre5

v0.9.0-pre6

v0.9.0-pre7

v0.9.0-pre8

v0.9.0-pre9

v0.9.0-rc1

v0.9.0-rc2

v0.9.0-rc3

v0.9.1

v0.9.10

v0.9.2

v0.9.3

v0.9.4

v0.9.5

v0.9.6

v0.9.7

v0.9.8

v0.9.9

Database specific

vanir_signatures_modified

"2026-07-15T16:00:31Z"

vanir_signatures

[
    {
        "signature_type": "Line",
        "target": {
            "file": "src/sail-codecs/xwd/xwd.c"
        },
        "deprecated": false,
        "source": "https://github.com/happyseafox/sail/commit/36aa5c7ec8a2bb35f6fb867a1177a6f141156b02",
        "id": "CVE-2026-40492-37962320",
        "signature_version": "v1",
        "digest": {
            "line_hashes": [
                "241914563982233639573845007159297089324",
                "295817320788695645281346781011607923799",
                "292825153532519996765145851580766437850"
            ],
            "threshold": 0.9
        }
    },
    {
        "signature_type": "Line",
        "target": {
            "file": "src/sail-codecs/xwd/helpers.c"
        },
        "deprecated": false,
        "source": "https://github.com/happyseafox/sail/commit/36aa5c7ec8a2bb35f6fb867a1177a6f141156b02",
        "id": "CVE-2026-40492-4341807d",
        "signature_version": "v1",
        "digest": {
            "line_hashes": [
                "301172747459491402306297918240814752710",
                "302421592605300366635941206248779060068",
                "74789464625873683996409345570762591823",
                "247752627975517855410946776263564758809",
                "170276404050264280440372485395218640317",
                "95229939895371536688137017804749238078",
                "37515935817804880849288679035941040941",
                "248394860716996669598131846278211538510",
                "301723293624276253928488806541747997667",
                "176348866057720317713467114476473176628",
                "11301665131726034708162836816131527854",
                "314800525921609777004113325435404543896"
            ],
            "threshold": 0.9
        }
    },
    {
        "signature_type": "Function",
        "target": {
            "file": "src/sail-codecs/xwd/helpers.c",
            "function": "xwd_private_read_pixels"
        },
        "deprecated": false,
        "source": "https://github.com/happyseafox/sail/commit/36aa5c7ec8a2bb35f6fb867a1177a6f141156b02",
        "id": "CVE-2026-40492-6523eecd",
        "signature_version": "v1",
        "digest": {
            "function_hash": "68601468689675830584704341915669920656",
            "length": 1802.0
        }
    },
    {
        "signature_type": "Function",
        "target": {
            "file": "src/sail-codecs/xwd/xwd.c",
            "function": "sail_codec_load_seek_next_frame_v8_xwd"
        },
        "deprecated": false,
        "source": "https://github.com/happyseafox/sail/commit/36aa5c7ec8a2bb35f6fb867a1177a6f141156b02",
        "id": "CVE-2026-40492-a9d4d239",
        "signature_version": "v1",
        "digest": {
            "function_hash": "90113702793324592564658174144569046510",
            "length": 2212.0
        }
    }
]

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40492.json"