NVD / CVE Program· CNA mitre

CVE-2023-36377: Buffer Overflow vulnerability in mtrojnar osslsigncode v.2.3 and before allows a local attacker to execute arbitrary code via a crafted .exe

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.30% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: osslsigncode (Debian:10) 2.0+really2.5-4+deb10u1; osslsigncode (Debian:11) 2.5-4~deb11u1; osslsigncode (Debian:12) 2.3.0-1.

Low priority for now. Upgrade to osslsigncode (Debian:10) 2.0+really2.5-4+deb10u1; osslsigncode (Debian:11) 2.5-4~deb11u1; osslsigncode (Debian:12) 2.3.0-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Buffer Overflow vulnerability in mtrojnar osslsigncode v.2.3 and before allows a local attacker to execute arbitrary code via a crafted .exe, .sys, and .dll files.

HighCVSS 7.8 · v3.1—No exploit Fix available

Published: Jul 3, 2023
Updated: Jun 17, 2026
EPSS: 0.3% · 22th percentile
CWE: CWE-120

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.3%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
osslsigncode project	osslsigncode	cpe:2.3:a:osslsigncode_project:osslsigncode

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

osslsigncode project osslsigncode2.3

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:10	osslsigncode	before 2.0+really2.5-4+deb10u1	2.0+really2.5-4+deb10u1
Debian:11	osslsigncode	before 2.5-4~deb11u1	2.5-4~deb11u1
Debian:12	osslsigncode	before 2.3.0-1	2.3.0-1

Same product

osslsigncode project: all records

Other highest-scoring records for the same primary product.

CVE-2025-70888An issue in mtrojnar Osslsigncode affected at v2.10 and before allows a remote attacker to escalate privileges via the osslsigncode.c compon
39Monitor
CVE-2026-39853osslsigncode has a Stack Buffer Overflow via Unbounded Digest Copy During Signature Verification
31Monitor
CVE-2026-39856osslsigncode has an Out-of-Bounds Read via Unvalidated Section Bounds in PE Page Hash Calculation
22Monitor

Published before and after this one in the same product

Later →CVE-2026-39855Apr 9, 2026 · osslsigncode has an Integer Underflow in PE Page Hash Calculation Can Cause Out-of-Bounds Read
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
debian:osslsigncode	2.3.0-1 · Debian:12	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

mtrojnar/osslsigncodecompare 2.2...2.3

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

The bug in code

The whole CWE-120 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1char buf[256];
2memcpy(buf, pkt->data, pkt->len);

Fixed

1char buf[256];
2if (pkt->len > sizeof(buf)) {
3  return -EINVAL;
4}
5memcpy(buf, pkt->data, pkt->len);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:48 PM UTC

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References

github.com/mtrojnar/osslsigncode/compare/2.2...2.3

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records