CVE-2023-0215 — openssl-src
HIGHCVE-2023-0215 is a high-severity (CVSS 7.5) Use After Free vulnerability in openssl-src. A fix is available for openssl-src — see the affected versions and patch details below.
Use-after-free following BIO_new_NDEF
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-0215.
EPSS Exploitation Probability
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.
How urgent is this, really
CVE-2023-0215 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
openssl-src🦀openssl-srcReal-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
The public API function BIO_new_NDEF is a helper function used for streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL to support the SMIME, CMS and PKCS7 streaming capabilities, but may also be called directly by end user applications.
The function receives a BIO from the caller, prepends a new BIO_f_asn1 filter BIO onto the front of it to form a BIO chain, and then returns the new head of the BIO chain to the caller. Under certain conditions, for example if a CMS recipient public key is invalid, the new filter BIO is freed and the function returns a NULL result indicating a failure. However, in this case, the BIO chain is not properly cleaned up and the BIO passed by the caller still retains internal pointers to the previously freed filter BIO. If the caller then goes on to call BIO_pop() on the BIO then a use-after-free will occur. This will most likely result in a crash.
This scenario occurs directly in the internal function B64_write_ASN1() which may cause BIO_new_NDEF() to be called and will subsequently call BIO_pop() on the BIO. This internal function is in turn called by the public API functions PEM_write_bio_ASN1_stream, PEM_write_bio_CMS_stream, PEM_write_bio_PKCS7_stream, SMIME_write_ASN1, SMIME_write_CMS and SMIME_write_PKCS7.
Other public API functions that may be impacted by this include i2d_ASN1_bio_stream, BIO_new_CMS, BIO_new_PKCS7, i2d_CMS_bio_stream and i2d_PKCS7_bio_stream.
The OpenSSL cms and smime command line applications are similarly affected.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | openssl-src | all versions | 111.25.0cargo update -p openssl-src --precise 111.25.0 |
| 🦀crates.io | openssl-src | ≥ 300.0.0&&< 300.0.12 | 300.0.12cargo update -p openssl-src --precise 300.0.12 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for openssl-src, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update openssl-src to 111.25.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-0215 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-0215 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-0215. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This flaw was found in the OpenSSL library within the BIO_new_NDEF function, which is used for ASN.1 data streaming. The flaw is a use-after-free issue that happens when an error occurs while setting up a BIO chain. In this case, the filter BIO is freed, but the original BIO still holds a reference to it. If the…
| Product | Fixed in | Advisory |
|---|---|---|
| JBoss Core Services for RHEL 8 | jbcs-httpd24-openssl-1:1.1.1k-14.el8jbcs | RHSA-2023:3354 |
| Red Hat Enterprise Linux 8 | edk2-0:20220126gitbb1bba3d77-4.el8 | RHSA-2023:2932 |
| Red Hat Enterprise Linux 8 | openssl-1:1.1.1k-9.el8_7 | RHSA-2023:1405 |
| Red Hat Enterprise Linux 8.6 Extended Update Support | edk2-0:20220126gitbb1bba3d77-2.el8_6.1 | RHSA-2023:4128 |
| Red Hat Enterprise Linux 8.6 Extended Update Support | openssl-1:1.1.1k-9.el8_6 | RHSA-2023:3408 |
| Red Hat Enterprise Linux 9 | openssl-1:3.0.1-47.el9_1 | RHSA-2023:0946 |
| Red Hat Enterprise Linux 9 | edk2-0:20221207gitfff6d81270b5-9.el9_2 | RHSA-2023:2165 |
| Red Hat Enterprise Linux 9.0 Extended Update Support | openssl-1:3.0.1-46.el9_0 | RHSA-2023:1199 |
Frequently Asked Questions
Is CVE-2023-0215 in your dependencies?
O3 Security finds CVE-2023-0215 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.