Malicious PDF — malware analysis report

Static analysis result for SHA-256 77779a741c96c8d4…

MALICIOUS

PDF

107.1 KB Created: 2021-05-15 14:59:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 89a30b602126bcb1389c713f89fd0ec3 SHA-1: 235da078513b730d5b78d540d54c1189ec275871 SHA-256: 77779a741c96c8d4b797c4abbea5fe3b9ecaaf4ba6228052c48100dfc1a649b3
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting, and one primary URL that appears to be part of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body, though heavily obfuscated, contains keywords related to 'jammer' and 'wkhtmltopdf', suggesting a lure to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • 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 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.
  • 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.
  • 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://bologen.ru/strik?utm_term=how+to+block+a+jammer PDF link annotation
    • https://numeroluxovuz.weebly.com/uploads/1/3/4/7/134733954/108d0124.pdfIn PDF document text
    • http://tokio-2020.fun/dupenepolubojon3hxf.pdfIn PDF document text
    • https://foxewazijibaj.weebly.com/uploads/1/3/1/3/131379544/b980a2c28d3422.pdfIn PDF document text
    • http://nonly.xyz/motumisavikadediiirt.pdfIn PDF document text
    • https://wojulifurezusek.weebly.com/uploads/1/3/1/4/131438898/bafiteki-bekekina-bipediwedumit.pdfIn PDF document text
    • https://mifafuriladivu.weebly.com/uploads/1/3/4/7/134733471/7457498.pdfIn PDF document text
    • http://blankid.ru/fuvokujedijivupufilokinojmahw.pdfIn PDF document text
    • http://povulofi.mywebcommunity.org/kejodibirorujejutuzexag.pdfIn PDF document text
    • http://changepass.online/ukulele_strumming_patterns_4_4d4fg6.pdfIn PDF document text
    • https://mizevazorabij.weebly.com/uploads/1/3/5/3/135347525/luletipopa.pdfIn PDF document text
    • http://fofumumitem.medianewsonline.com/56775879113.pdfIn PDF document text
    • http://gelokan.sportsontheweb.net/53595144513.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/641a7a94-e8d6-4264-a72c-961365d79b28/common_core_sheets_multiplying_unit_fractions_with_number_line.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/45ae7ac3-608d-4f53-a0ac-b24d484e79f4/88982362166.pdfIn PDF document text
    • https://0cfe495c-9a5f-46a1-a5f3-fb21b6211bac.filesusr.com/ugd/7aabb2_18e1f27908344749bd88c709d2acf176.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5290272-acbb-4f0d-896b-41bffed7f934/what_order_do_you_read_the_halo_books.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/05e5881d-0cfb-4c6e-863c-5870b60c3674/bugaminobuwi.pdfIn PDF document text
    • https://s3.amazonaws.com/wenobagupexekap/crash_bandicoot_full_game_pc.pdfIn PDF document text
    • https://s3.amazonaws.com/ginutu/32009301779.pdfIn PDF document text
    • https://s3.amazonaws.com/vovabagubajegeb/bayesian_probability_for_dummies.pdfIn PDF document text
    • https://s3.amazonaws.com/bagokiko/possessive_case_exercises.pdfIn PDF document text
    • https://e148473a-3d1a-46f8-b788-fbc1f5af68d4.filesusr.com/ugd/e1e70b_98b73d478b0a434084744b7aa0388036.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xokebore/rental_property_depreciation_guide_ato.pdfIn PDF document text
    • https://80820154-e864-4b0c-832b-212b24169927.filesusr.com/ugd/c12414_013bf4eccab84bedaf52d1f5395ac3fa.pdf?index=trueIn PDF document text
    • https://2c9641c8-5874-4869-9b94-f1378e60aa6b.filesusr.com/ugd/efc1f6_2793da378ec6456cb87e7ad46e9b6b15.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00017af2.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x17AF2 21352 bytes
SHA-256: 24c493d36f2acaf9075dae0571ff08fca68b26bead89fb6e2ebd5d2a55e37421
font_00_sfnt_off00013cf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CF0 5100 bytes
SHA-256: 5a103be7ad183c0860d454997bee7bc7ec446e61de379206a13856691b1855aa
font_01_sfnt_off00014e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E48 14344 bytes
SHA-256: 25122e5f9099e69ef462ca9d22aa86daa9b70c3f3a30be0a3ec754b61fc010bb