CVE-2020-36316Public exploit

Application crash via malformed PKCS#1 padding

Published Apr 7, 2021 · Updated Aug 4, 2024

Buffer overflow in RELIC before 2021-04-03 allows attackers to crash consuming applications via malformed PKCS#1 v1.5 signatures. The pad_pkcs1() routine accepts fewer than eight padding bytes and overwrites pad_len, causing size minus pad_len to exceed the h1 buffer during a later write. A consuming application must verify an attacker-supplied signature; the demonstrated consequence is a segmentation fault.

CVSS severity5.5
Medium
EPSS probability1.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in RELIC before 2021-04-03 allows attackers to crash consuming applications via malformed PKCS#1 v1.5 signatures. The pad_pkcs1() routine accepts fewer than eight padding bytes and overwrites pad_len, causing size minus pad_len to exceed the h1 buffer during a later write. A consuming application must verify an attacker-supplied signature; the demonstrated consequence is a segmentation fault.

The record

CVE
CVE-2020-36316
Published
Apr 7, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

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.

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No observations available

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

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1499.004Application or System Exploitation

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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