Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fed5951c85abdd8…

MALICIOUS

PDF

44.9 KB Created: 2021-05-13 09:31:22 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-26
MD5: edf592a7a49a6790781474cd07759fc5 SHA-1: 8b4f1ea71ecb2bbb53a4f2e4fba5525662966a64 SHA-256: 5fed5951c85abdd8081b16a226ffa43be8e53e6f1ae7b58121129bd4934b00f5
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to redirector infrastructure, specifically advertising 'coin master free spins' and 'robux hacks'. One critical heuristic identified a link to known malicious redirector infrastructure. The document body, though partially corrupted, contains similar lure text and URLs. The presence of numerous links suggests an attempt to drive traffic to potentially malicious sites, aligning with a phishing or scam lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9632

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.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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 https://netcdn.xyz/app/406889139/coin-master-free-spins-1-coin-master-game-hack In PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-hack-no-verification_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-spin-link-for-coin-master_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/earn-free-robux-for-roblox_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-roblox-glasses_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-hack-mod-apk-android-1_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/earn-robux-for-roblox_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/get-free-spins-coin-master-2021_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/how-to-get-free-robux-not-a-scam_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-apk-hack-download_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-spin-and-coin_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/legitimate-coin-master-free-spins-apk_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/how-to-get-free-spins-and-coins-on-coin-master_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/spin-coin-master-free_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-coin_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-spin-hack-no-verification_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-roblox-script-executor_GM431946152.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-spins-gratis_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/how-to-get-free-spins-in-coin-master_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-coins-and-spins_GM406889139.pdfIn PDF document text
    • https://www.st-peters-alton.staffs.sch.uk/admin/ckfinder/userfiles/files/free-spins-coin-master-2021-app_GM406889139.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004abb.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4ABB 24904 bytes
SHA-256: 03f32d7f1411545e88e0f59fcade4d408f0a3003aca683aaebd809a1835246d0
font_01_sfnt_off00008351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8351 17992 bytes
SHA-256: 6d8d99a319dc3508354c514a9dfb36b9314a67d789b860417dc5e127b03e5453
font_02_sfnt_off0000a46d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA46D 3264 bytes
SHA-256: e32c06502c11b52acb5e814091c5fdbffd1e2a904ac7a9cfb8b5b180bd139088