How severe is GHSA-32fw-gq77-f2f2?

No CVSS score has been assigned to GHSA-32fw-gq77-f2f2 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-32fw-gq77-f2f2?

GHSA-32fw-gq77-f2f2 affects the following packages: github.com/eclipse/paho.mqtt.golang (Go). Ecosystems affected: Go.

How do I fix GHSA-32fw-gq77-f2f2?

Update github.com/eclipse/paho.mqtt.golang to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-32fw-gq77-f2f2 is resolved across your whole dependency graph.

How do I detect GHSA-32fw-gq77-f2f2 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/eclipse/paho.mqtt.golang. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-32fw-gq77-f2f2 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-32fw-gq77-f2f2?

O3 pinpoints whether GHSA-32fw-gq77-f2f2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-32fw-gq77-f2f2 actively exploited in the wild?

No public exploit code has been indexed for GHSA-32fw-gq77-f2f2 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-32fw-gq77-f2f2?

GHSA-32fw-gq77-f2f2 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 9th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-32fw-gq77-f2f2?

GHSA-32fw-gq77-f2f2 is classified as CWE-197 (CWE-197), CWE-681 (CWE-681). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-32fw-gq77-f2f2 published, and has it been updated?

GHSA-32fw-gq77-f2f2 was published on December 2, 2025 and was last updated on February 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-32fw-gq77-f2f2: paho.mqtt.golang

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk9th percentile+0.15%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

🐹github.com/eclipse/paho.mqtt.golang

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

In Eclipse Paho Go MQTT v3.1 library (paho.mqtt.golang) versions <=1.5.0 UTF-8 encoded strings, passed into the library, may be incorrectly encoded if their length exceeds 65535 bytes. This may lead to unexpected content in packets sent to the server (for example, part of an MQTT topic may leak into the message body in a PUBLISH packet).

The issue arises because the length of the data passed in was converted from an int64/int32 (depending upon CPU) to an int16 without checks for overflows. The int16 length was then written, followed by the data (e.g. topic). This meant that when the data (e.g. topic) was over 65535 bytes then the amount of data written exceeds what the length field indicates. This could lead to a corrupt packet, or mean that the excess data leaks into another field (e.g. topic leaks into message body).

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/eclipse/paho.mqtt.golang`	all versions	1.5.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/eclipse/paho.mqtt.golang. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/eclipse/paho.mqtt.golang to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-32fw-gq77-f2f2 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-32fw-gq77-f2f2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-32fw-gq77-f2f2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

In Eclipse Paho Go MQTT v3.1 library (paho.mqtt.golang) versions <=1.5.0 UTF-8 encoded strings, passed into the library, may be incorrectly encoded if their length exceeds 65535 bytes. This may lead to unexpected content in packets sent to the server (for example, part of an MQTT topic may leak into the message body in a PUBLISH packet). The issue arises because the length of the data passed in was converted from an int64/int32 (depending upon CPU) to an int16 without checks for overflows. The int16 length was then written, followed by the data (e.g. topic). This meant that when the data (e.g

O3 Security · Impact-Aware SCA

Is GHSA-32fw-gq77-f2f2 in your dependencies?

O3 detects GHSA-32fw-gq77-f2f2 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

GHSA-32fw-gq77-f2f2