Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c1979d23b0b1159…

MALICIOUS

PDF

80.1 KB Created: 2021-03-31 11:15:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: cc7b47ce9f8384f20839c379482c48a4 SHA-1: 984d826d01565e4d4f24d215942370fc8d709ac0 SHA-256: 4c1979d23b0b11591256f6fce98b033c382648afc1619aa66e491754acb87696
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://mezovuduw.ru/strik?utm_term=standard+normal+distribution+table+negative+and+positive PDF link annotation
    • https://kemolarutu.weebly.com/uploads/1/3/4/6/134685450/riwuxomobupov_tigarusiju.pdfIn PDF document text
    • https://tiriwubesunadew.weebly.com/uploads/1/3/0/7/130739346/lagirezifiweten.pdfIn PDF document text
    • http://bcpzonasegura10beta-viabcp.com/103618522301xtrs.pdfIn PDF document text
    • https://sufudavinor.weebly.com/uploads/1/3/1/3/131381021/kimebol_xupidadofolu_gotikod_zedifewesa.pdfIn PDF document text
    • http://nadahul.ru/will_a_bluetooth_dongle_work_on_xbox_onexc7bl.pdfIn PDF document text
    • http://meblik.su/how_to_change_battery_in_liftmaster_security_plus_keypad129j5.pdfIn PDF document text
    • http://numidib.22web.org/46659394834.pdfIn PDF document text
    • https://pomapufawupufus.weebly.com/uploads/1/3/5/3/135397804/dadotaxid_mejasur_tabenisowisusa_vomuguzavimow.pdfIn PDF document text
    • http://copyright-security-ig.com/86855913154hyyy5.pdfIn PDF document text
    • https://zugasunisozabij.weebly.com/uploads/1/3/4/7/134759734/tipafolul.pdfIn PDF document text
    • http://hookup750.website/hard_sat_reading_passages1s2b1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/pizivurapab/is_a_vitamix_blender_worth_the_money.pdfIn PDF document text
    • http://guvenaverelud.epizy.com/liszt_la_campanella_piano_sheet_music.pdfIn PDF document text
    • https://s3.amazonaws.com/roxawo/chickpea_salad_nutritional_information.pdfIn PDF document text
    • https://8607b5f8-c2b2-49b7-a314-b17bd4efff40.filesusr.com/ugd/d99252_3d3d4bb180154c8f91af02b640701c99.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/118e8d08-f03c-45d3-b6f8-b60e085c59ba/42596138019.pdfIn PDF document text
    • https://0eaabcdb-938a-45a6-85a3-1a7d796bbcdd.filesusr.com/ugd/8d6d25_e6a7999eb8e74a2c949b90bd4ef2e9ef.pdf?index=trueIn PDF document text
    • http://gepijelemerafin.rf.gd/pre_gastric_sleeve_diet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a74bad7b-2f61-40fb-a5db-4af98b1bcb00/stihl_hs45_hedge_trimmer_fuel_tank.pdfIn PDF document text
    • https://8d6920c1-aef5-45ed-b1a0-e693d63948fb.filesusr.com/ugd/0a593f_38e899a28b8747d7bf2580b4b9776749.pdf?index=trueIn PDF document text
    • https://c7bff75e-0a19-4817-9d47-fca4cf08161b.filesusr.com/ugd/3b6424_0acb46f355ba45e6ab32af1eaaa36e73.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/87271793-35f8-4574-9c86-03e085e32117/63118773364.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/60aee114-e513-45f3-9e62-ec7a4c6679e9/what_was_the_first_rap_song_to_win_a_grammy.pdfIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f92c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92C 5584 bytes
SHA-256: edd206acb8224dda678e1a44a2141ea8541713cf9e38062bf3100f58a048ebd6
font_01_sfnt_off00010c10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C10 11224 bytes
SHA-256: 6dc9c08f547b21dd61937e850d386d7baf554dd8f905427b0ec0c2c74791de22