CVE-2021-22948

Exp

Vulnerability in the generation of session IDs in revive-adserver < 5.3.0, based on the cryptographically insecure uniqid() PHP function. Under some circumstances, an attacker could theoretically be able to brute force session IDs in order to take over a specific account.

Published: 2021-09-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-22948 is rated High Exploit Risk (63.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.37%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-22948

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-22948

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-10-04 0.62% 0.37% -0.25%
2 2025-10-01 0.55% 0.62% +0.08%
3 2025-09-04 0.55%

Full EPSS history (27 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-22948

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 4.2 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-22948

Affected software / configurations for CVE-2021-22948

Vendor Product Version Raw CPE
revive-adserver revive_adserver < 5.3.0 cpe:2.3:a:revive-adserver:revive_adserver:*:*:*:*:*:*:*:*
revive-adserver revive_adserver 5.3.0 cpe:2.3:a:revive-adserver:revive_adserver:5.3.0:rc1:*:*:*:*:*:*

References for CVE-2021-22948

cvelogic Threat Intelligence