Malicious PDF — malware analysis report

Static analysis result for SHA-256 a97f5a8ba7bdb295…

MALICIOUS

PDF

79.6 KB Created: 2021-06-01 03:26:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dc394145231be4e97a6f3f1565e6417a SHA-1: 77b73bef3d623ddc1f913799116944a309b5c132 SHA-256: a97f5a8ba7bdb295008365eed3cb8a3a030961d4fd8b5e7280d78b0c4b5a2cc8
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a critical heuristic identifying it as a "PDF_SEO_LINK_FARM". One of the primary external links, https://ketchas.ru/pbw?utm_term=kettlebell+fat+loss+program+pdf, suggests a lure related to a fitness program. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or a scam. No scripts were extracted, but the PDF structure itself is used to host a large number of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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
  • 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://ketchas.ru/pbw?utm_term=kettlebell+fat+loss+program+pdf
    • https://sujarusokebukok.weebly.com/uploads/1/3/1/4/131437349/gasejuzu.pdf
    • https://jitugexe.weebly.com/uploads/1/3/0/9/130969989/7030998.pdf
    • https://badikixokatapi.weebly.com/uploads/1/3/0/7/130739740/votaxarijejufu.pdf
    • https://nasorigabewa.weebly.com/uploads/1/3/4/5/134519214/1232496.pdf
    • https://lojavexir.weebly.com/uploads/1/3/5/9/135963097/334654.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/de8e4f9b-6f2b-433f-bbf4-527a1ada02fb/a_composers_guide_to_game_music.pdf
    • https://uploads.strikinglycdn.com/files/7b2b558a-c1be-4551-8e1d-4d28c717c87a/46919332764.pdf
    • https://uploads.strikinglycdn.com/files/2ed564c9-1905-41ac-acad-4b4b7fb882e1/8010836427.pdf
    • https://uploads.strikinglycdn.com/files/3e27954e-b218-450c-903e-1ceea4aa806c/present_perfect_simple_exercises_with_answers.pdf
    • https://uploads.strikinglycdn.com/files/954215a4-2708-4a43-88c0-7b5596253612/how_to_break_curses_over_your_life.pdf
    • https://uploads.strikinglycdn.com/files/5ef7efce-fd94-4f20-a7e9-79f5b28efa82/job_reference_letter_format.pdf
    • https://uploads.strikinglycdn.com/files/4fe7b1a9-e8ba-4514-aefc-d317345df709/wiwoguzulamogabeb.pdf
    • https://uploads.strikinglycdn.com/files/14f6bd4c-c6b1-4564-bc56-384cc78996f1/the_princess_bride_book_hardcover.pdf
    • http://sorawako.pbworks.com/w/file/fetch/144435711/fubutedakujazizazefenidat.pdf
    • https://uploads.strikinglycdn.com/files/40a5fe72-99ba-4b45-bbe3-7a120306abc5/marvel_cinematic_universe_upcoming_movie_timeline.pdf
    • https://uploads.strikinglycdn.com/files/b9fd378d-2f1c-4ee5-99fc-f466ab55b167/dell_bluetooth_driver_for_windows_7_64_bit_free_download_softonic.pdf
    • https://uploads.strikinglycdn.com/files/5cd1328e-2f28-4c7a-84f6-dd65febae634/mcgraw_hill_education_us_history_workbook_answers.pdf
    • http://dewubuk.pbworks.com/w/file/fetch/144422160/chal_mera_putt_2_full_movie_download_720p_filmywap.pdf
    • https://uploads.strikinglycdn.com/files/0fce0549-c7ba-4b90-b4de-8bd3749bd021/2007_dodge_caliber_repair_manual.pdf
    • https://uploads.strikinglycdn.com/files/d14ca4e6-7cfa-457e-8993-7a08be8951de/49110140279.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed73.bin
1d3e951d2d8155881d3350f40ab9b7470ff4bdb31e61ea1e28bf3adfeaf86712
pdf-font-stream PDF embedded font (sfnt) at offset 0xED73 5104 bytes
font_01_sfnt_off0000fed5.bin
9c74ad9330751e33e9eb20be42601d74b418fe074daf9497ed464be072da2833
pdf-font-stream PDF embedded font (sfnt) at offset 0xFED5 10512 bytes
font_02_sfnt_off000122e3.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x122E3 4324 bytes