CVE-2024-21484Public exploitNetwork attack vector

RSA plaintext recovery via decryption timing oracle

Published Jan 22, 2024 · Updated Oct 21, 2024

Observable discrepancy in jsrsasign before 11.0.0 allows remote attackers to decrypt RSA ciphertexts through timing measurements. KJUR.crypto.Cipher.decrypt leaks the raw RSA result's bit length for PKCS#1 v1.5 and OAEP inputs, while PKCS#1 v1.5 processing also leaks plaintext length through execution time. Exploitation requires many ciphertext probes processed with the same private key and yields plaintext recovery without reported integrity impact.

CVSS severity7.5
High
EPSS probability0.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Observable discrepancy in jsrsasign before 11.0.0 allows remote attackers to decrypt RSA ciphertexts through timing measurements. KJUR.crypto.Cipher.decrypt leaks the raw RSA result's bit length for PKCS#1 v1.5 and OAEP inputs, while PKCS#1 v1.5 processing also leaks plaintext length through execution time. Exploitation requires many ciphertext probes processed with the same private key and yields plaintext recovery without reported integrity impact.

The record

CVE
CVE-2024-21484
Published
Jan 22, 2024
Updated
Oct 21, 2024
Vendor
jsrsasign project
Product
jsrsasign
Classifications
CWE-203, CAPEC-189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 22, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2024Record 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=0 <*
  2. Affected versionversion=0 <11.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

jsrsasign project · jsrsasignversion=0 <*; version=0 <11.0.0

Published CVSS scores

7.5GitHubCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:L
5.9NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

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 exploitPublished

Weakness, pattern, technique

CWE-203Observable Discrepancy
CAPEC-189Black Box Reverse Engineering

Public exploit references

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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