Malicious PDF — malware analysis report

Static analysis result for SHA-256 c73be2f5417ce0d0…

MALICIOUS

PDF

75.0 KB Created: 2021-03-15 16:33:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 6e14c8b2ec4479812061b70836ad4300 SHA-1: b635fd86f0588d82c986195e0bcbbbe5858b6982 SHA-256: c73be2f5417ce0d07b54ce04be9fe4520a37d649ebf02f940678c85fc7401b7c
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://xezojetit.ru/123?utm_term=adverb+and+its+type+exercises+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4480895/normal_6012327d133fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384633/normal_6019b721127c5.pdfIn PDF document text
    • http://lofoporubatul.mygamesonline.org/libro_de_lecturas_primer_grado_primaria.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369305/normal_6041381ebf8f9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414502/normal_5fe89a5a3b23a.pdfIn PDF document text
    • https://wesojejupeledaw.weebly.com/uploads/1/3/4/4/134446418/vavakoromemovivizexu.pdfIn PDF document text
    • https://sukaxivex.weebly.com/uploads/1/3/4/8/134895869/b97cfa.pdfIn PDF document text
    • https://tekevifumufov.weebly.com/uploads/1/3/0/7/130739519/6679793.pdfIn PDF document text
    • http://vunixifatirami.22web.org/63598180043.pdfIn PDF document text
    • https://cdn.sqhk.co/nemuvefik/nphhe1h/mubenerekurevu.pdfIn PDF document text
    • https://cdn.sqhk.co/bitaxukezor/bpHaYge/rail_rush_2_game_free_download.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489615/normal_600cfcb35647f.pdfIn PDF document text
    • https://cdn.sqhk.co/jigitovewuk/zeT9mgc/lineage_2_revolution_best_class_for_solo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/3defc14d-0bc5-4947-a027-8ca7f2fed028/volunteer_fire_department_training_calendar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0fbcb641-26df-4f71-899a-3a276fe0619a/how_to_change_a_belt_on_a_stackable_washer_and_dryer.pdfIn PDF document text
    • http://lugimeviguv.myartsonline.com/40418009959.pdfIn PDF document text
    • http://xewaxal.epizy.com/82113478102.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6583c7b-67fc-4221-bff4-6b3fd00e997f/adobe_premiere_pro_cc_2018_free_trial_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00c92d7a-553d-49c6-a604-1c11822e851e/what_happened_to_julius_caesar_and_cleopatra.pdfIn PDF document text
    • http://kedumuwimafam.rf.gd/54373595421.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA76 5156 bytes
SHA-256: df60a6ec97f7b604a32e449c2cb7785d9334225ea91313ca90e75b9f4ba0af88
font_01_sfnt_off0000ec0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0C 10628 bytes
SHA-256: a6c225caa153252dc8a13e8dbb29bf9a7a59a2e33bcf3a8a9c182eddc265131a
font_02_sfnt_off0001102e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1102E 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361