CVE-2021-22901
What it is
curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection. A malicious server can use this in rare unfortunate circumstances to potentially reach remote code execution in the client. When libcurl at run-time sets up support for TLS 1.3 session tickets on a connection using OpenSSL, it stores pointers to the transfer in-memory object for later retrieval when a session ticket arrives. If the connection is used by multiple transfers (like with a reused HTTP/1.1 connection or multiplexed HTTP/2 connection) that first transfer object might be freed before the new session is established on that connection and then the function will access a memory buffer that might be freed. When using that memory, libcurl might even call a function pointer in the object, making it possible for a remote code execution if the server could somehow manage to get crafted memory content into the correct place in memory.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 63.5% chance of exploitation in the next 30 days (EPSS). Higher than most.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 63.5% in the next 30 days (EPSS).
- Severity: 8.1 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 63.5% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Haxx Curl ≤ 7.76.1
- Oracle Communications Cloud Native Core Binding Support Function 1.11.0
- Oracle Communications Cloud Native Core Network Function Cloud Native Environment 1.10.0
- Oracle Communications Cloud Native Core Network Repository Function 1.15.0
- Oracle Communications Cloud Native Core Network Repository Function 1.15.1
- Oracle Communications Cloud Native Core Network Slice Selection Function 1.8.0
- Oracle Communications Cloud Native Core Service Communication Proxy 1.15.0
- Oracle Essbase < 11.1.2.4.047
Attack profile CVSS 3.1 · 8.1
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-22901.md and follow it. Check whether this project is affected by CVE-2021-22901. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://curl.se/docs/CVE-2021-22901.html
- https://github.com/curl/curl/commit/7f4a9a9b2a49547eae24d2e19bc5c346e9026479
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://curl.se/docs/CVE-2021-22901.html
- https://github.com/curl/curl/commit/7f4a9a9b2a49547eae24d2e19bc5c346e9026479
- https://www.oracle.com//security-alerts/cpujul2021.html
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-732250.pdf
- https://curl.se/docs/CVE-2021-22901.html
- https://github.com/curl/curl/commit/7f4a9a9b2a49547eae24d2e19bc5c346e9026479
- https://hackerone.com/reports/1180380
- https://security.netapp.com/advisory/ntap-20210723-0001/
- https://security.netapp.com/advisory/ntap-20210727-0007/
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-732250.pdf
- https://curl.se/docs/CVE-2021-22901.html
- https://github.com/curl/curl/commit/7f4a9a9b2a49547eae24d2e19bc5c346e9026479
- https://hackerone.com/reports/1180380
- https://security.netapp.com/advisory/ntap-20210723-0001/
- https://security.netapp.com/advisory/ntap-20210727-0007/
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://cert-portal.siemens.com/productcert/html/ssa-389290.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
- https://cert-portal.siemens.com/productcert/html/ssa-732250.html