How severe is CVE-2021-45703?

No CVSS score has been assigned to CVE-2021-45703 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2021-45703?

CVE-2021-45703 affects the following packages: tectonic_xdv (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2021-45703?

Update tectonic_xdv to 0.1.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45703 is resolved across your whole dependency graph.

How do I detect CVE-2021-45703 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tectonic_xdv. 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 CVE-2021-45703 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 CVE-2021-45703?

O3 pinpoints whether CVE-2021-45703 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 CVE-2021-45703 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-45703 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 type of vulnerability is CVE-2021-45703?

CVE-2021-45703 is classified as CWE-908 (CWE-908). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-45703 published, and has it been updated?

CVE-2021-45703 was published on June 17, 2022 and was last updated on February 3, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

Withdrawn — this advisory has been retracted

🦀 crates.io

Not in CISA KEV

CVE-2021-45703

Fix: tectonic-typesetting/tectonic@cdff034

CVE-2021-45703 is a CWE-908 vulnerability in tectonic_xdv. O3 Security confirms whether CVE-2021-45703 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Duplicate Advisory: `Read` on uninitialized buffer may cause UB ('tectonic_xdv' crate)

Also known asGHSA-qwvx-c8j7-5g75RUSTSEC-2021-0112

Published

Jun 17, 2022

Updated

Feb 3, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Feb 3, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Real-World Exposure

1 pkg affected

🦀tectonic_xdv

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

Description

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-qwvx-c8j7-5g75. This link is maintained to preserve external references.

Original Description

Affected versions of this crate passes an uninitialized buffer to a user-provided Read implementation.

Arbitrary Read implementations can read from the uninitialized buffer (memory exposure) and also can return incorrect number of bytes written to the buffer. Reading from uninitialized memory produces undefined values that can quickly invoke undefined behavior.

The problem was fixed in commit cdff034 by zero-initializing the buffer before passing it to a user-provided Read implementation.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`tectonic_xdv`	all versions	0.1.12

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tectonic_xdv. 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 tectonic_xdv to 0.1.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45703 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 CVE-2021-45703 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 CVE-2021-45703. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-qwvx-c8j7-5g75. This link is maintained to preserve external references. ## Original Description Affected versions of this crate passes an uninitialized buffer to a user-provided `Read` implementation. Arbitrary `Read` implementations can read from the uninitialized buffer (memory exposure) and also can return incorrect number of bytes written to the buffer. Reading from uninitialized memory produces undefined values that can quickly invoke undefined behavior. The problem was fixed in commit `cdff034` b

O3 Security · Impact-Aware SCA

Is CVE-2021-45703 in your dependencies?

O3 detects CVE-2021-45703 across crates.io 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