Malicious PDF — malware analysis report

Static analysis result for SHA-256 59d138ad9195cf9f…

MALICIOUS

PDF

79.4 KB Created: 2021-03-24 14:30:48 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: ec1e07f7646bb50a45a35f590b41735b SHA-1: dbd76e03d0abe375b498397e16fac23ec8e2b6a0 SHA-256: 59d138ad9195cf9ff35ee4c1cc67140ca09843c486d182dd678da60b11e72668
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many pointing to disposable domains, which is characteristic of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for SEO manipulation or to serve malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about its purpose beyond the embedded links.

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://soxebez.ru/award?keyword=acetilcolina+que+es+pdf PDF link annotation
    • http://opensalon.xyz/4345850278664atl.pdfIn PDF document text
    • http://streamsweets.com/microsoft_visual_studio_2010_free_download_offline_installer44bg6.pdfIn PDF document text
    • http://edayafar.xyz/aws_solution_architect_cheat_sheet_2020iwbfr.pdfIn PDF document text
    • http://arendaavto.taxi/mackie_cfx20_mkii_mixer_manual6dbp7.pdfIn PDF document text
    • http://serdyukov.pro/65834273864cr3nl.pdfIn PDF document text
    • http://lnstagram-verifedbadge.com/9167133374021ehj.pdfIn PDF document text
    • http://bonmarket.site/56141303675an0xg.pdfIn PDF document text
    • http://garderob-podolsk.ru/424998807436542d.pdfIn PDF document text
    • http://fredo.bike/impossible_space_best_weaponsg7frb.pdfIn PDF document text
    • http://3-bureaureport.info/how_do_i_program_my_spectrum_remote_to_my_insignia_tvr5zmm.pdfIn PDF document text
    • http://takipleskazan.org/bsa_wood_carving_merit_badge_pamphlet69w1m.pdfIn PDF document text
    • http://btsworld.org/describir_el_escribir_daniel_cassanybca6i.pdfIn PDF document text
    • http://mainsale.pro/kobalt_10_inch_sliding_compound_miter_saw_partsobmnl.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/9c7c3e0d-e16b-433c-86fe-7016b4363bd7/69257453004.pdfIn PDF document text
    • https://79ab8074-8148-4faa-9219-f6cdfa35bc15.filesusr.com/ugd/99e004_7395fc97622f409fbd761fe24f955a08.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1cc8886c-c9b2-45f6-bfb3-157d25cdcc58/let_the_right_one_in_full_movie_online_eng_sub.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5118421b-66f8-4a41-b37c-983b865b94f4/historia_del_escudo_de_san_jose_costa_rica.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee23c8b7-8e14-44af-b5ad-0c6bae7c731f/logic_pro_x_macbook_pro_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6055067-7476-431f-a257-dbe8d01ac7ca/diziro.pdfIn PDF document text
    • https://a26b494c-4f54-4b9d-aaa3-e02d462d315a.filesusr.com/ugd/c6268f_b6a33c245ea14d829f588a2473494404.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4bbd121-c6d0-4881-980f-4aabce78077b/2_the_chemistry_of_life_chapter_test_a.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50b2cc3e-a79c-4fce-ae87-51e653f3bdb0/how_to_draw_realistic_eyebrows.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/416a0508-fa68-4f6d-8836-67e06acfbfda/how_to_tie_knots_for_necklace.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_off0000f52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52C 5168 bytes
SHA-256: f4fcb679c3ad36e889907e93dc272f67a0c146b125aa00949ddca093d1c87a30
font_01_sfnt_off000106db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106DB 13248 bytes
SHA-256: e14d5627849e6c74d82b0e4f02548ea14ef5b3d8d5eb017d974ceb9630c30e5e