Malicious PDF — malware analysis report

Static analysis result for SHA-256 23bde98d6dec9e78…

MALICIOUS

PDF

75.0 KB Created: 2021-03-07 02:59:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: afb6f4b5334e91f75d0c20785a6bff48 SHA-1: 440a89b4448e9eaf71bafa1e00146144f512efd3 SHA-256: 23bde98d6dec9e781e9067139e20c05bf5a70522d67f1cbc78c0cb6400bcfcb4
184 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links pointing to various external PDF documents hosted on disposable domains. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, and one of the embedded URLs is known to lead to malicious redirector infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=ipega+bluetooth+gaming+controller+review In PDF document text
    • https://xoxajunun.weebly.com/uploads/1/3/4/3/134351876/gexasufuvenipej.pdfIn PDF document text
    • https://ronabamipiboti.weebly.com/uploads/1/3/4/5/134598089/zusen-mukerabuv-waputinikufot.pdfIn PDF document text
    • https://cdn.sqhk.co/ropobemuma/haF1Vjg/can_you_escape_2_level_24.pdfIn PDF document text
    • http://nufizurob.22web.org/tumasejegowemexaxaja.pdfIn PDF document text
    • https://rakiletapaleta.weebly.com/uploads/1/3/1/8/131856645/noguzowuvet-rixugevemedifiv-jimiwumetow.pdfIn PDF document text
    • http://wabixekere.iblogger.org/how_many_calories_in_a_large_caramel_craze_latte.pdfIn PDF document text
    • https://wusaworapivuwor.weebly.com/uploads/1/3/4/6/134659128/viralire.pdfIn PDF document text
    • http://lavogomibonit.iblogger.org/free_workshop_agenda_template_ppt.pdfIn PDF document text
    • https://peziwotikiju.weebly.com/uploads/1/3/4/6/134602895/tivuvumabeze.pdfIn PDF document text
    • https://cdn.sqhk.co/tosuwukiwate/jDV8DNy/amazon_white_gold_rings.pdfIn PDF document text
    • https://zevakevo.weebly.com/uploads/1/3/5/4/135400716/8dd62227543d94.pdfIn PDF document text
    • https://vetafewilede.weebly.com/uploads/1/3/1/4/131408572/ca0aa343ad.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fugewep.rf.gd/narapenigolumurabogire.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6ac0d62-8de3-44bc-a1c1-561cacdaa6d4/41728424057.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a169ad6-c554-4dae-9bf9-96cd421c19fc/kifubosukasorinaviwidum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0799635c-9c4f-436e-9ea2-f754a9bc166f/trig_equations_cheat_sheet.pdfIn PDF document text
    • http://xujogefup.rf.gd/chogada_tara_song_bestwap._link.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/845889c7-1331-4ab9-b97f-7e365d5b984c/54377628404.pdfIn PDF document text
    • http://tuwafexom.epizy.com/are_gps_obsolete.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7d7d441-c3b9-44cb-92d7-8e86eda6aa69/83323750233.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_off0000e957.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE957 5396 bytes
SHA-256: c71fcc8c09ab8ef6b38586f467b70b95fcb827e68f07a85d4d7287c0515b1813
font_01_sfnt_off0000fb99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB99 10316 bytes
SHA-256: 1977f35bd77a7387a8b52534518d374ecb0c71094cd05540f61379b681b1d834