Malicious PDF — malware analysis report

Static analysis result for SHA-256 cff095ef7916122c…

MALICIOUS

PDF

81.6 KB Created: 2021-04-17 02:40:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 7856180558fcf13dc55f52c4f310e9e9 SHA-1: 28f949b5f7d9de68f3d096c0790fc86282119af1 SHA-256: cff095ef7916122ca60bc6be915335c42ace3fd7d5389042f26303ffed01340c
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous external URLs pointing to other PDFs hosted on various domains, some of which are disposable. The primary purpose appears to be SEO manipulation or distributing further malicious content, rather than direct user interaction within the document itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://jacksth.ru/strik?utm_term=best+octavia+butler+books+reddit PDF link annotation
    • https://cdn.sqhk.co/muwazubivotu/Qha1Rje/davobekamewefuvazil.pdfIn PDF document text
    • https://cdn.sqhk.co/bovokolel/8PjeLFN/deriwusigonipurigegozepe.pdfIn PDF document text
    • https://cdn.sqhk.co/pugepavofu/o29GiiA/viral_video_views_booster_free.pdfIn PDF document text
    • https://cdn.sqhk.co/rovujesox/Rgie1ie/aftab_e_alam_book_free.pdfIn PDF document text
    • http://sagaguzasonip.iblogger.org/93885211199.pdfIn PDF document text
    • https://cdn.sqhk.co/wixefawoz/iighjcY/amul_ice_cream_store_near_me.pdfIn PDF document text
    • http://roman-holidays.shop/what_is_the_difference_between_gen_4_and_gen_5_glocksxllpo.pdfIn PDF document text
    • http://shoppingyxplus.xyz/tutorial_itext_javakmuwo.pdfIn PDF document text
    • https://cdn.sqhk.co/raninogozo/hjegdjh/sodoton.pdfIn PDF document text
    • http://prosale.company/6.5_creedmoor_load_data_hodgdon_superformance27t6o.pdfIn PDF document text
    • http://terem.space/download_game_football_manager_2020_mod_apk_offlinejk591.pdfIn PDF document text
    • http://businessoutsourcing.org/610027517289otqe.pdfIn PDF document text
    • http://air-calm2.club/so_good_almond_milk_nutritional_informationh8hcs.pdfIn PDF document text
    • http://sun-italy.space/how_to_sync_firestick_remote_to_tv_volumee93n9.pdfIn PDF document text
    • http://shopsupergood.site/91527704594142ak.pdfIn PDF document text
    • https://cdn.sqhk.co/godajaxox/KheyiVl/canadian_visa_application_form_for_pakistani.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8fa10226-37c2-454d-bd65-ced70ecbf0c4.filesusr.com/ugd/c34aa9_dc601511541d4a549973cb7a391c71af.pdf?index=trueIn PDF document text
    • https://8650d040-a33d-467d-a608-6706f181f11b.filesusr.com/ugd/61b8bf_de63656c19cd41f99076e12c2bae69ab.pdf?index=trueIn PDF document text
    • http://vedujekobizu.rf.gd/network_interface_card_tutorial.pdfIn PDF document text
    • http://rovigugidolu.epizy.com/rupitabaruruzovagaku.pdfIn PDF document text
    • http://vazolola.rf.gd/70165851042.pdfIn PDF document text
    • https://72dfff08-f6cb-4f5d-aaac-ebe71175d6a6.filesusr.com/ugd/c268f7_5b90818a7ce844c081a57473bd4ce39c.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D1 5244 bytes
SHA-256: a4d57277b2255153bf29dfc304f65c439ebcec6558e9fa8183d56e44a72867bb
font_01_sfnt_off00010ab7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB7 1956 bytes
SHA-256: 56a53b80793a57ae0a2ff185a047ca1e37b57a0e8d64e13b04e3c35c58b8895d
font_02_sfnt_off000113da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113DA 10660 bytes
SHA-256: ecbda999a4bc3b77fd4cb44a4b274d282c05f49b44a0f26d6ce3244b9f089bb7