Information disclosure via reused AES-CTR nonce
Published Jan 20, 2023 · Updated Apr 3, 2025
Information disclosure in MediaWiki CheckUser before 1.35.9 and in 1.36.0 through 1.38.4 and 1.39.0 allows remote attackers to decrypt JWT data. TokenManager encrypts predictable JSON payloads with AES-CTR while reusing one session-stored nonce, so XORing two ciphertexts exposes their plaintext relationship. Exploitation requires obtaining at least two tokens from the same session; disclosed plaintext can include CheckUser reasons, target usernames, or IP addresses.
Summary
What happened
Information disclosure in MediaWiki CheckUser before 1.35.9 and in 1.36.0 through 1.38.4 and 1.39.0 allows remote attackers to decrypt JWT data. TokenManager encrypts predictable JSON payloads with AES-CTR while reusing one session-stored nonce, so XORing two ciphertexts exposes their plaintext relationship. Exploitation requires obtaining at least two tokens from the same session; disclosed plaintext can include CheckUser reasons, target usernames, or IP addresses.
The record
- CVE
- CVE-2023-22912
- Published
- Jan 20, 2023
- Updated
- Apr 3, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-330
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 20, 2023CVE publishedPublication date reported by the CVE source.
- Apr 3, 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?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- CheckUser nonce-reuse JWT decryption demonstrationproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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