Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea3d3ed18982fa35…

MALICIOUS

PDF

85.7 KB Created: 2021-04-20 23:18:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 29528b38dc2347c1dfbfaa7b67fcae05 SHA-1: d423dbc49e73eb6a6a535dfc95089a52ffdf1941 SHA-256: ea3d3ed18982fa35f5f1f0842c6ca809517a070809148ac076d13e0ebf939613
222 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam operation. The presence of urgency and invoice lures further supports a phishing or scamming attempt. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 9

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://dafemum.ru/strik?utm_term=barbri+mpre+questions+harder
    • https://cdn-cms.f-static.net/uploads/4366324/normal_6065fa78a1871.pdf
    • https://cdn-cms.f-static.net/uploads/4445544/normal_60184eccef5a4.pdf
    • https://gogadumipoti.weebly.com/uploads/1/3/1/0/131070618/5842950.pdf
    • http://sugameloxufe.mywebcommunity.org/nugomadawajimelad.pdf
    • http://suziterunedoloj.sportsontheweb.net/asbaq_e_tareekh.pdf
    • https://kabuxezalexafa.weebly.com/uploads/1/3/0/8/130814122/7253927.pdf
    • https://cdn.sqhk.co/jebozibiru/Xf0ibid/xorulidetes.pdf
    • https://cdn.sqhk.co/wirumedaba/ftjKmhc/best_box_game_ps4_vr.pdf
    • http://larijasetejupaz.mypressonline.com/ejercicios_de_movimiento_articular.pdf
    • https://diboboxu.weebly.com/uploads/1/3/4/3/134330346/wirisa.pdf
    • https://puwiwasoz.weebly.com/uploads/1/3/2/6/132695956/1966690.pdf
    • https://cdn-cms.f-static.net/uploads/4402712/normal_60243afaca610.pdf
    • https://bufofeguwozeder.weebly.com/uploads/1/3/0/7/130775144/votojuvorobifuzij.pdf
    • https://mofesotuju.weebly.com/uploads/1/3/4/7/134712265/dafar.pdf
    • https://kobipisi.weebly.com/uploads/1/3/4/3/134312725/rafefib_viwezutefafub.pdf
    • https://jumugegapu.weebly.com/uploads/1/3/0/8/130814907/vimil_bupuvopilarafib.pdf
    • https://cdn.sqhk.co/gufojakig/nghlpii/zanufasum.pdf
    • https://cdn.sqhk.co/denirinodo/hT5iicb/smash_it_up_badminton.pdf
    • https://rudusixan.weebly.com/uploads/1/3/0/7/130775573/3837404.pdf
    • https://xikigojajutu.weebly.com/uploads/1/3/4/3/134385057/bevogoze.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/gazijewevan/38635550352.pdf
    • https://s3.amazonaws.com/napejaxosinages/xitunajuxelupazi.pdf
    • https://s3.amazonaws.com/tikoweravisixu/speak_by_laurie_halse_anderson_online_book.pdf
    • https://s3.amazonaws.com/bubeto/83128138230.pdf
    • https://s3.amazonaws.com/runuzitexokol/play_games_free_bubble_shooter.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010e92.bin
bcc1d5f7d5ae9fdd88a6b4ab8ad3d1a7c1f5b7ac47db6358d0fe6fa79f03573c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E92 5480 bytes
font_01_sfnt_off000120fb.bin
e6fa547b1a44945f2bafb0e2f2b7174217760094efc6c326c8931676d8e0f794
pdf-font-stream PDF embedded font (sfnt) at offset 0x120FB 11768 bytes