BIG-IP: Use of Insufficiently Random Values
CVE-2022-26071 is a high-severity use of insufficiently random values vulnerability in BIG-IP from F5, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 16.1.2.2, 15.1.5.1, 14.1.4.6 as the first without the flaw, so updating BIG-IP to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.07% chance of exploitation within 30 days, higher than 65% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update BIG-IP to 16.1.2.2 or 15.1.5.1 or 14.1.4.6 or 13.1.5, whichever matches your release line, or a later version.
- Read the advisory on support.f5.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| F5 | BIG-IP | 12.1.x; 11.6.x; 16.1.x up to, but not including, 16.1.2.2; 15.1.x up to, but not including, 15.1.5.1; 14.1.x up to, but not including, 14.1.4.6; 13.1.x up to, but not including, 13.1.5 | 16.1.2.2, 15.1.5.1, 14.1.4.6, 13.1.5 |
| F5 | Big-ip Access Policy Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Advanced Firewall Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Analytics | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Application Acceleration Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Application Security Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Domain Name System | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Fraud Protection Service | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Global Traffic Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Link Controller | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Local Traffic Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
| F5 | Big-ip Policy Enforcement Manager | 11.6.1; 11.6.2; 11.6.3; 11.6.4; 11.6.5; 12.1.0; 12.1.1; 12.1.2; and 23 more ranges | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.4 | High | CNA (f5.com) |
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 5.0 | Medium | NVD |
Official description
On F5 BIG-IP 16.1.x versions prior to 16.1.2.2, 15.1.x versions prior to 15.1.5.1, 14.1.x versions prior to 14.1.4.6, 13.1.x versions prior to 13.1.5, and all versions of 12.1.x and 11.6.x, a flaw in the way reply ICMP packets are limited in the Traffic Management Microkernel (TMM) allows an attacker to quickly scan open UDP ports. This flaw allows an off-path remote attacker to effectively bypass source port UDP randomization. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use of Insufficiently Random Values
The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.
How developers prevent this class of flaw
- Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds. In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts. Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a random enough number.
- Consider a PRNG that re-seeds itself as needed from high quality pseudo-random output sources, such as hardware devices.
- Use products or modules that conform to FIPS 140-2 to avoid obvious entropy problems. Consult FIPS 140-2 Annex C (Approved Random Number Generators).
More Use of Insufficiently Random Values vulnerabilities (CWE-330)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in BIG-IP
- 9.8 Critical severity
F5 BIG-IP APM Heap-based Buffer Overflow Exploited
- 8.8 High severity
- 7.5 High severity
- 8.7 High severity
- 8.7 High severity
- 7.5 High severity
Recent Use of Insufficiently Random Values vulnerabilities
- 9.8 Critical severity
- 9.1 Critical severity
- 9.1 Critical severity
- 7.5 High severity
- 9.1 Critical severity
- 9.8 Critical severity
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