CVE-2026-50012

Squid is a caching proxy for the Web. Prior to 7.6, due to an improper input validation bug in cache digest reply handling (peerDigestSwapInMask in src/peerdigest.cc), Squid is vulnerable to a heap-based buffer overflow: a cache digest's on-the-wire size may be larger than the masksize declared within the digest, so a trusted peer sending a maliciously crafted reply to a cachedigest request message can trigger the overflow. This attack is limited to Squid instances compiled with the --enable-cache-digests option and configured with cachepeer entries. This issue is fixed in version 7.6.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-122",
        "CWE-20"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50012.json"
}

References

Affected packages

Git / github.com/squid-cache/squid

Affected ranges

Type

GIT

Repo

https://github.com/squid-cache/squid

Events

Introduced

Fixed

a440c2af73b394fc31539a4f85bfb5d5ed47dd9a

Fixed

19fcfe922717c8b255270c032dcde4071c003bcd

Database specific

{
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ],
    "cpe": "cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "7.6"
        }
    ]
}

Affected versions

4.*

4.15-20210522-snapshot

4.15-20210523-snapshot

4.15-20210524-snapshot

4.15-20210525-snapshot

4.15-20210527-snapshot

5.*

5.0.6-20210522-snapshot

5.0.6-20210523-snapshot

5.0.6-20210524-snapshot

5.0.6-20210525-snapshot

5.0.6-20210527-snapshot

6.*

6.0.0-20210522-master-snapshot

6.0.0-20210523-master-snapshot

6.0.0-20210524-master-snapshot

6.0.0-20210525-master-snapshot

6.0.0-20210527-master-snapshot

Other

HISTORIC_RELEASES

M-staged-PR161

M-staged-PR164

M-staged-PR170

M-staged-PR176

M-staged-PR179

M-staged-PR181

M-staged-PR182

M-staged-PR186

M-staged-PR189

M-staged-PR193

M-staged-PR195

M-staged-PR196

M-staged-PR198

M-staged-PR199

M-staged-PR200

M-staged-PR202

M-staged-PR206

M-staged-PR208

M-staged-PR209

M-staged-PR210

M-staged-PR218

M-staged-PR220

M-staged-PR221

M-staged-PR225

M-staged-PR227

M-staged-PR229

M-staged-PR230

M-staged-PR235

M-staged-PR237

M-staged-PR238

M-staged-PR239

M-staged-PR241

M-staged-PR242

M-staged-PR252

M-staged-PR255

M-staged-PR258

M-staged-PR264

M-staged-PR266

M-staged-PR267

M-staged-PR268

M-staged-PR274

M-staged-PR276

M-staged-PR293

M-staged-PR294

M-staged-PR295

M-staged-PR299

M-staged-PR306

M-staged-PR314

M-staged-PR319

M-staged-PR342

M-staged-PR345

M-staged-PR348

M-staged-PR351

M-staged-PR359

M-staged-PR364

M-staged-PR365

M-staged-PR366

M-staged-PR370

M-staged-PR372

M-staged-PR373

M-staged-PR375

M-staged-PR376

SQUID_3_0_PRE1

SQUID_3_0_PRE2

SQUID_3_0_PRE3

SQUID_3_0_PRE4

SQUID_3_0_PRE5

SQUID_3_0_PRE6

SQUID_3_0_PRE7

SQUID_3_0_RC1

SQUID_3_5_27

SQUID_4_0_1

SQUID_4_0_10

SQUID_4_0_11

SQUID_4_0_12

SQUID_4_0_13

SQUID_4_0_14

SQUID_4_0_15

SQUID_4_0_16

SQUID_4_0_2

SQUID_4_0_3

SQUID_4_0_4

SQUID_4_0_5

SQUID_4_0_6

SQUID_4_0_7

SQUID_4_0_8

SQUID_4_0_9

SQUID_7_0_1

SQUID_7_0_2

SQUID_7_1

SQUID_7_2

SQUID_7_3

SQUID_7_4

SQUID_7_5

take00

Database specific

vanir_signatures_modified

"2026-07-22T04:19:30Z"

vanir_signatures

[
    {
        "target": {
            "file": "src/peer_digest.cc"
        },
        "digest": {
            "line_hashes": [
                "229550311145704481924451770564358024578",
                "221920238537344078225207842802955983578",
                "166847730665289552997050079606109205227"
            ],
            "threshold": 0.9
        },
        "signature_version": "v1",
        "signature_type": "Line",
        "deprecated": false,
        "id": "CVE-2026-50012-8204a6ea",
        "source": "https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd"
    },
    {
        "target": {
            "function": "peerDigestSwapInMask",
            "file": "src/peer_digest.cc"
        },
        "digest": {
            "length": 725.0,
            "function_hash": "250827425887602908147261629380683058993"
        },
        "signature_version": "v1",
        "signature_type": "Function",
        "deprecated": false,
        "id": "CVE-2026-50012-839f3062",
        "source": "https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd"
    }
]

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-50012.json"