Malicious PDF — malware analysis report

Static analysis result for SHA-256 0cbde75340d0805f…

MALICIOUS

PDF

78.4 KB Created: 2021-06-09 18:55:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 5838b98a1c972dfd3a20963c4dc5840a SHA-1: e73ea10f755022fff61d2034ba0bc73ff37b1aba SHA-256: 0cbde75340d0805f8c55f6182df0bbea541c5d21dab1d15d725a5cc61491195c
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a LOLBin command-execution lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://druttle.ru/123?utm_term=slope+of+a+line%2523+1+worksheet+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4391013/normal_6052d9d77e79c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472788/normal_6067602e1790c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444366/normal_600b6321474cb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473640/normal_6048dc3fd3048.pdfIn macro / runtime command snippet
    • https://cdn-cms.f-static.net/uploads/4408348/normal_602142484ec3e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446765/normal_60061a79c1e2f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4468551/normal_5fe05a54865b7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480383/normal_605d92e513556.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448733/normal_60bd7834d64fe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4530578/normal_5fcf34c92ac0b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402267/normal_5fd0b68c15766.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sipibujewadu.pbworks.com/w/file/fetch/144663960/5269756448.pdfIn PDF document text
    • http://sofutikajen.pbworks.com/w/file/fetch/144460701/lista_de_comandos_cmd_windows.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a52ddb07-6db5-4bff-ba29-b93f834d45b3/rain_bird_5000_nozzle_chart.pdfIn PDF document text
    • http://subazim.pbworks.com/w/file/fetch/144544527/zezoxitefusaf.pdfIn PDF document text
    • http://xifilipisi.pbworks.com/w/file/fetch/144684246/pubg_mobile_lite_mod_apk_unlimited_health_download.pdfIn PDF document text
    • http://pozapagula.pbworks.com/f/blockman_go_apk_download_1.34.1.pdfIn PDF document text
    • http://xizegopago.pbworks.com/f/21883161182.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dff6ed80-23fe-44c1-982d-b90a104ef5a9/marvel_avengers_infinity_war_movies_counter.pdfIn PDF document text
    • http://bemulopawed.pbworks.com/f/duwuxomosokij.pdfIn PDF document text
    • http://nigezid.pbworks.com/f/cat_mario_unblocked_games_77.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d466512-2971-4ad0-95c0-67583583986f/58221945156.pdfIn PDF document text
    • http://mukibilevejo.pbworks.com/w/file/fetch/144468567/94809260847.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
    • https://uploads.strikinglycdn.com/files/a52dIn macro / runtime command snippet
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f67d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF67D 4724 bytes
SHA-256: 3f3b96c2316eb41106444ca68bb44c724fdb49605c58d64e16a2e037e28d71c8
font_01_sfnt_off000106a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A9 11008 bytes
SHA-256: 77ecc9780fbe355c4756b1cc9ad79327f04f0e285b04d81a9e083abf5525c8f3