CVE-2026-77220

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Source
https://cve.org/CVERecord?id=CVE-2026-77220
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77220.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-77220
Downstream
Published
2026-08-21T20:54:34Z
Modified
2026-08-27T19:14:10Z
Severity
  • 7.1 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
PDFio < 1.6.5 Dangling Pointer via Dictionary String-Formatting
Details

PDFio before 1.6.5 contains a dangling pointer vulnerability in the dictionary string-formatting function that stores a pointer to a stack-local buffer in the document dictionary without copying the string value. In multi-threaded or pooled-request environments, attackers or concurrent users can trigger stack memory reuse across requests, causing cross-tenant document content corruption by silently overwriting one caller's dictionary string values with another caller's data.

Database specific 
{
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
        "CWE-825"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77220.json"
}
References

Affected packages

Git / github.com/michaelrsweet/pdfio

Affected ranges

Type
GIT
Repo
https://github.com/michaelrsweet/pdfio
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
5102eddff28d9b605f3e6783d50ad380f61f692e
Fixed
22b9afc800c5833f9e851e35938972bd4c76a357
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.6.5"
        }
    ],
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ]
}

Affected versions

v1.*
v1.0.0
v1.0.1
v1.0b1
v1.0b2
v1.1.0
v1.1.1
v1.1.2
v1.1.3
v1.1.4
v1.2.0
v1.3.0
v1.3.1
v1.3.2
v1.4.0
v1.4.1
v1.5.0
v1.5.1
v1.5.2
v1.6.0
v1.6.1
v1.6.2
v1.6.3
v1.6.4

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77220.json"
vanir_signatures 
[
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "206220656076517917598020857657619829177",
                "303718665690998273257748695389723119175",
                "326349271487051918019348789262440632780",
                "288685422910406038857624548261886084666"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-77220-8ebc7005",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/michaelrsweet/pdfio/commit/22b9afc800c5833f9e851e35938972bd4c76a357",
        "target": {
            "file": "pdfio-dict.c"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "110038082440133928243647618735064586845",
                "153942206308715827523636941930677953745",
                "301186365577948111165377126548766545259",
                "88692615793945068479985108822729888282"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-77220-a93dae83",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/michaelrsweet/pdfio/commit/5102eddff28d9b605f3e6783d50ad380f61f692e",
        "target": {
            "file": "pdfio.h"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "225031063541702359332826341943304795865",
            "length": 317
        },
        "id": "CVE-2026-77220-c284ece5",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/michaelrsweet/pdfio/commit/22b9afc800c5833f9e851e35938972bd4c76a357",
        "target": {
            "file": "pdfio-dict.c",
            "function": "pdfioDictSetStringf"
        }
    }
]
vanir_signatures_modified 
"2026-08-27T19:14:10Z"