CVE-2025-3933Network attack vector

Service interruption via Donut regex backtracking

Published Jul 11, 2025 · Updated Jul 11, 2025

ReDoS in Hugging Face Transformers 4.51.3 and earlier allows remote attackers to interrupt Donut document processing with crafted tokens. DonutProcessor.token2json searches untrusted token text with the <s_(.*?)> pattern, whose lazy wildcard repeatedly backtracks when a closing delimiter is absent or delayed. Applications must pass attacker-controlled Donut token output to this method; excessive CPU use can hang document processing or its hosting service.

CVSS severity5.3
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

ReDoS in Hugging Face Transformers 4.51.3 and earlier allows remote attackers to interrupt Donut document processing with crafted tokens. DonutProcessor.token2json searches untrusted token text with the <s_(.*?)> pattern, whose lazy wildcard repeatedly backtracks when a closing delimiter is absent or delayed. Applications must pass attacker-controlled Donut token output to this method; excessive CPU use can hang document processing or its hosting service.

The record

CVE
CVE-2025-3933
Published
Jul 11, 2025
Updated
Jul 11, 2025
Vendor
Hugging Face
Product
Hugging Face Transformers
Classifications
CWE-1333, CAPEC-492, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 11, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 11, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <4.52.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Hugging Face · Hugging Face Transformersversion=unspecified <4.52.1

Published CVSS scores

5.3GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
CAPEC-492Regular Expression Exponential Blowup
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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