CVE-2026-8463
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
NVD Score used
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-126, CWE-191
- Updated
- 2026-11-02
CVE List
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-126, CWE-191
- Updated
- 2026-11-02
EUVDEUVD-2026-29956
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
EUVD-2026-29956- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-3p6c-7qjr-35x9
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in...
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
GHSA-3p6c-7qjr-35x9- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-126
- Updated
- 2026-11-02
OSVALPINE-CVE-2026-8463
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
ALPINE-CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-03
OSV
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.
The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.
A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-126, CWE-191
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-8463
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input. The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte. A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
DEBIAN-CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-8463
5.3
Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input. The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte. A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.
- Record
UBUNTU-CVE-2026-8463- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
perl-crypt-argon2Alpine:v3.24 |
0.017 up to 0.031-r0 | 0.031-r0 |
libcrypt-argon2-perlDebian:12 |
All versions, plus listed versions 0.013-10.020-10.022-10.026-10.029-10.030-10.031-10.032-1 |
None known |
libcrypt-argon2-perlDebian:13 |
All versions, plus listed versions 0.030-10.031-10.032-1 |
None known |
libcrypt-argon2-perlDebian:14 |
before 0.031-1, plus listed versions 0.030-1 |
0.031-1 |
libcrypt-argon2-perlUbuntu:24.04:LTS |
All versions, plus listed versions 0.013-10.020-10.020-1build10.020-1build20.020-1build3 |
None known |
libcrypt-argon2-perlUbuntu:25.10 |
All versions, plus listed versions 0.029-1build10.030-1 |
None known |
libcrypt-argon2-perlUbuntu:26.10 |
All versions, plus listed versions 0.030-10.031-10.031-1build1 |
None known |
libcrypt-argon2-perlUbuntu:26.04:LTS |
All versions, plus listed versions 0.030-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-8463 is a medium vulnerability (CVSS 5.3) in Leont Crypt::argon2, published May 13, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 25th percentile. Fixed in perl-crypt-argon2 0.031-r0.
References
github.com/Leont/crypt-argon2/commit/92eac03ce63d541e0ead7ea5a89b9b67ce0c0e64.patch
metacpan.org/release/LEONT/Crypt-Argon2-0.031/changes
openwall.com/lists/oss-security/2026/05/13/4
nvd.nist.gov/vuln/detail/CVE-2026-8463
github.com/advisories/GHSA-3p6c-7qjr-35x9
security.alpinelinux.org/vuln/CVE-2026-8463
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cpan.org/modules
github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8463.json
github.com/Leont/crypt-argon2
security-tracker.debian.org/tracker/CVE-2026-8463
ubuntu.com/security/CVE-2026-8463
cve.org/CVERecord?id=CVE-2026-8463
lists.security.metacpan.org/cve-announce/msg/40006926
github.com/Leont/crypt-argon2/commit/92eac03ce63d541e0ead7ea5a89b9b67ce0c0e64