Malicious PDF — malware analysis report

Static analysis result for SHA-256 537212e7f2747543…

MALICIOUS

PDF

35.6 KB Created: 2021-06-25 11:51:01 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 5715a937027337695855745c63e3ebc8 SHA-1: 3a48ccba7e18d67b30ab19e78093e4d99f6a4776 SHA-256: 537212e7f27475434fa6dd0d9531387f41df6b9ba6ec31ccfa51ce648d9beda0
180 Risk Score

Malware Insights

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

The PDF contains a malformed stream and multiple links to known malicious redirectors, specifically advertising "free Roblox gift card numbers" and "game hacks". The primary malicious URL identified is http://netcdn.co/app/431946152/free-roblox-gift-card-numbers-game-hack. This suggests the document is designed to lure users to potentially malicious websites, likely for credential harvesting or malware distribution, leveraging a common social engineering tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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.
  • 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.
  • 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.co/app/431946152/free-roblox-gift-card-numbers-game-hack In PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/roblox-data-breach_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/free-coin-master-spin-and-coin-link_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/coin-master-free-coins-and-spins-daily-summary_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/free-coins-and-spins-for-coin-master_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/how-to-hack-roblox-to-get-robux_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/robux-generator-com_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/free-money-and-spins-coin-master_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/roblox-jailbreak-free-cash_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/free-coins-on-coin-master-without-verification_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/free-robux-legit_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/tiktok-free-liker_GM835599320.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/minecraft-xbox-360-free_GM479516143.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/car-dealer-roblox-hack_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/roblox-get-free-groups_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/are-there-ways-to-get-robux-for-free_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/huskybuckscom-free-robux_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/roblox-free-play-no-download_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/pahto-forces-roblox-rank-hack_GM431946152.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/static-moonactive-net-rewards_GM406889139.pdfIn PDF document text
    • http://www.technibuild-group.com/uploaded_files/userfiles/files/how-to-hack-assasssain-in-roblox-youtube_GM431946152.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
font_00_sfnt_off00003431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3431 22076 bytes
SHA-256: 1e0930fca3834325d105b31049de727b3b00998598d774f4ee0bef721a8f6da9
font_01_sfnt_off00006508.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6508 19448 bytes
SHA-256: 718b9f50ed5b0d966682deb4ef73e04098d9c5c79eb144aa760464ee9fdcfe5c