CVE-2026-44166 | Pocketbase: Account pre-hijacking via OAuth2 unverfied->verified autolinking upgrade

Pocketbase is an open source web backend written in go. Prior to 0.22.42 and 0.37.4, in some situations, if an attacker knows the email address of the victim they can create and link an unverified PocketBase user in advance by authenticating with one of the OAuth2 app providers, e.g. "A". When the victim gets invited or decides to sign up to your app on their own with provider "B" (PocketBase OAuth2 auth requires to be with a different provider because we don't allow multiple OAuth2 accounts from the same provider to be associated to a single PocketBase user), the user created previously by the attacker will be autolinked, upgraded to "verified" and its old password reset. This vulnerability is fixed in 0.22.42 and 0.37.4.

Published: 2026-05-12 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-44166 is rated Low Risk (27.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.19%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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

Exploit prediction scoring system (EPSS) score for CVE-2026-44166

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 2026-06-15 0.03% 0.19% +0.15%
2 2026-05-20 0.05% 0.03% -0.02%
3 2026-05-18 — 0.05% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-44166

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 4.0 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:P)
A user has to participate (for example click/open/approve).
Vulnerable system confidentiality impact (VC:L)
Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:L)
Limited availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
 — — [email protected]
7.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L 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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 2.8 4.7 [email protected]

Weakness enumeration for CVE-2026-44166

GitHub Security Advisory for CVE-2026-44166

GHSA-pq7p-mc74-g65w · Severity: medium · Ecosystem: go — PocketBase vulnerable to account pre-hijacking via OAuth2 unverfied->verified autolinking upgrade

Affected software / configurations for CVE-2026-44166

Vendor Product Version Raw CPE
pocketbase pocketbase < 0.22.42 cpe:2.3:a:pocketbase:pocketbase:*:*:*:*:*:go:*:*
pocketbase pocketbase >= 0.23.0, < 0.37.4 cpe:2.3:a:pocketbase:pocketbase:*:*:*:*:*:go:*:*

References for CVE-2026-44166

cvelogic Threat Intelligence