Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c28204f3b4b1c80…

MALICIOUS

PDF

76.0 KB Created: 2021-04-09 03:45:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: dadbcd399718b576bc5778800bf7a337 SHA-1: 89099e368b706cfc7a8d264c83801357ef3e9c20 SHA-256: 9c28204f3b4b1c809d4638714e040b2128f88f8411417399743ae2489089e310
186 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It contains a significant number of external links, many hosted on disposable domains, indicating a link farm or phishing lure. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content. The presence of numerous external URIs and the overall structure strongly suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://fokemale.ru/strik?utm_term=what+does+the+4+hand+sign+mean+urban+dictionary PDF link annotation
    • http://naturfresh.space/how_much_do_driving_examiners_get_paidwa6ns.pdfIn PDF document text
    • https://runobutadafe.weebly.com/uploads/1/3/0/9/130969205/8087768.pdfIn PDF document text
    • http://migriruy.ru/actor_who_played_baby_grinchmclkn.pdfIn PDF document text
    • https://gixebodaloru.weebly.com/uploads/1/3/1/3/131379223/lanosa.pdfIn PDF document text
    • https://cdn.sqhk.co/bolomekurufe/bghShdd/dilefakadavibewodor.pdfIn PDF document text
    • https://cdn.sqhk.co/ripalufix/ihidt3h/8455224312.pdfIn PDF document text
    • https://vekafikag.weebly.com/uploads/1/3/5/9/135986004/c9f285e75073.pdfIn PDF document text
    • http://yyyyyyhhhhh.space/xabanidaroginivaribemi2xt7h.pdfIn PDF document text
    • https://zatenumidepav.weebly.com/uploads/1/3/0/7/130776458/wesovosin.pdfIn PDF document text
    • http://cethq.xyz/ryobi_bc30_carburetorc5ghl.pdfIn PDF document text
    • https://vebuleme.weebly.com/uploads/1/3/4/3/134321641/nelobovijerazonisu.pdfIn PDF document text
    • http://relax35.ru/how_to_use_nikon_sb_800_flashwuqfg.pdfIn PDF document text
    • https://cdn.sqhk.co/bipujawojeli/MmPidha/icymi_meaning_slang.pdfIn PDF document text
    • http://tokio-2020.fun/wosomop93f81.pdfIn PDF document text
    • https://cdn.sqhk.co/kagumuzom/MeEirjc/download_vortex_cloud_gaming_mod_apk_unlimited_money.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/7cc26fe0-0f21-4d28-9a27-9e398a786723/fewovepejipojisozi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bc63853-c6f8-4d41-8326-44cc0248f5f6/beurer_wrist_blood_pressure_monitor_instructions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/33f3237f-e037-407a-9de5-d3bd4198286a/realtek_hd_audio_driver_windows_10_dell.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/98e2d296-396e-4808-8cc3-bffe58975483/what_is_a_giant_sub_at_jersey_mikes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/782b131e-26bd-4bdb-87ea-45f9cc99a80f/jumping_over_the_broom_movie_cast.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0b31e702-aa52-4818-af15-d7badb2a0505/89552461987.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_off0000e87d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87D 5664 bytes
SHA-256: 37a842e6cd650e1bea45c6ed1d26858c86e4474183a37e9d363e6ca0da8eee3b
font_01_sfnt_off0000fbb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB0 11604 bytes
SHA-256: 4ac47e0443650213e3cf4ed0ba666a662fb2e63939a88dfdbf4018a30253a469