Malicious PDF — malware analysis report

Static analysis result for SHA-256 88f48d6c8e172ca3…

MALICIOUS

PDF

250.7 KB Created: 2021-07-06 06:41:58 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 20d96e31a89e41edef007b19de288f46 SHA-1: 8d85c0678e07c9acb24ed0d5ed1947662f5c5f24 SHA-256: 88f48d6c8e172ca3ff7f4bcb705c5c43e1610fe7db8e740babf27b2b167faa35
278 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a critical heuristic indicating it links to a malicious redirector disguised as a 'free generator / game hack'. It also presents a fake CAPTCHA and impersonates the brand 'Apple' to trick users into clicking the malicious link. The document body, though heavily obfuscated, contains references to the malicious URL, reinforcing the phishing attempt.

Machine Learning

  • Nyx PDF Classifier clean score 0.0098

Heuristics 9

  • PDF links to a 'free generator / game hack' redirector critical PDF_GAME_HACK_REDIRECT_LURE
    PDF's clickable action targets a redirector of the form /app/<id>/<slug>-game-hack — the landing-page shape of a large SEO 'free spins / generator / game hack' lure family that funnels victims through rotating disposable hosts to a malware/scam payload. The multi-link variants also trip ML/link-farm rules; this catches the single-link variants that otherwise score clean. CRITICAL on its own: the /app/<id>/<slug>-game-hack path shape is unambiguous scam infra, and the host rotates so a host-list match can't be relied on.
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: http://netcdn.tw/app/1330123889/by-pubg-uc-free-game-hack.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://netcdn.tw/app/1330123889/by-pubg-uc-free-game-hack In PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/get-free-robux-instantly-no-human-verification_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/free-roblox-items-com_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/kupang/repository/free-robux-com_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/paper-mario-roleplay-roblox-cheat-engine_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/kupang/repository/free-roblox-adopt-me-accounts_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/free-roblox-police-uniform_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/robux-app_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/royal-high-school-roblox-how-to-gwet-free-mony_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/main/repository/2021-hacking-roblox_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/main/repository/free-robux-without-human-verification_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/how-to-hack-injustice-roblox_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/main/repository/how-to-get-free-robux-legit-with-proof_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/tp-hacks-script-roblox_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/kupang/repository/how-to-get-free-robux-2021-easy_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/how-to-make-a-minecraft-server-for-free-java_GM479516143.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/how-to-get-free-robux-new_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/how-long-are-you-banned-from-roblox-if-you-hack_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/kupang/repository/coinmaster-gps-user-review-coinmaster-coin-master-hack-pagedemo-index_GM406889139.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/ciawi/repository/how-to-hack-roblox-accounts_GM431946152.pdfIn PDF document text
    • http://lib.bppsdmp.pertanian.go.id/kupang/repository/how-do-you-get-minecraft-for-free_GM479516143.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_024_off00037dee.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x37DEE 26028 bytes
SHA-256: 55e8eb0d800c2e2e0ceb20350a06f2d673df3f4ca2318efaf7b16d1d6e1dc97b
font_01_sfnt_off0003bb2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3BB2F 18468 bytes
SHA-256: eb001765ad46b5c946228e21cf6254c3784e157298e6909e29893eacc78dca1e