Malicious PDF — malware analysis report

Static analysis result for SHA-256 5783f7f2fc611aff…

MALICIOUS

PDF

76.7 KB Created: 2021-05-13 11:04:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 3f5ed432a62078c9c0e3d6e92bab24fd SHA-1: 2164c300b20391f73eedea9627a48d64fdedc5a1 SHA-256: 5783f7f2fc611aff595a0e81578cf4af42ef5de4b50eedc822e87781e0962dc1
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The sample is identified as a malicious PDF by multiple heuristics and a machine learning classifier, specifically flagging it as a brand-impersonation credential phishing lure for UPS. The embedded URL `https://nipisod.ru/strik?utm_term=teeter+hang+ups+for+sale+craigslist` and the link to `https://mawurimi.weebly.com/uploads/1/3/4/6/134661678/5702235.pdf` are indicative of a phishing campaign. The document was authored using wkhtmltopdf, which is sometimes used to generate malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://mawurimi.weebly.com/uploads/1/3/4/6/134661678/5702235.pdf.
  • 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://nipisod.ru/strik?utm_term=teeter+hang+ups+for+sale+craigslist PDF link annotation
    • https://mawurimi.weebly.com/uploads/1/3/4/6/134661678/5702235.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4494138/normal_5fe0cd92cec6f.pdfIn PDF document text
    • http://kudikadip.getenjoyment.net/agendas_2020.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449406/normal_5ff8b12e58a8b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374372/normal_60418df0a5767.pdfIn PDF document text
    • https://joxunirefebemi.weebly.com/uploads/1/3/4/3/134319414/lotasudi.pdfIn PDF document text
    • http://tapozifokun.mywebcommunity.org/biztalk_server_tutorial.pdfIn PDF document text
    • https://dowisapi.weebly.com/uploads/1/3/4/2/134266119/89338648.pdfIn PDF document text
    • http://naturelofo.mypressonline.com/what_are_the_examples_of_literary_devices.pdfIn PDF document text
    • https://xalidanazate.weebly.com/uploads/1/3/6/0/136082238/1707139.pdfIn PDF document text
    • https://mojavopadagesit.weebly.com/uploads/1/3/5/3/135383036/puvubezopesaxigoxin.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401558/normal_5fd1c50a9d8bd.pdfIn PDF document text
    • http://mudixefibewab.mywebcommunity.org/zobilisiruvozuje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426697/normal_6016437a994bd.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://2aa0b900-127f-4603-a19a-6a731d3c9eb1.filesusr.com/ugd/5eaffa_6c8edea69e7046c6b4b5a5b64f74422c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jarirotexab/fatojetenafujaxejixapetew.pdfIn PDF document text
    • https://fd7a53fe-11c1-4e60-83ad-ac1bb997268f.filesusr.com/ugd/5cf23b_b4ec67a0de9f49e3b6f2b32a399d898f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nuvukivaxiren/dizedujuvelibiju.pdfIn PDF document text
    • http://kivarutumo.myartsonline.com/nitrate_ion_selective_electrode.pdfIn PDF document text
    • https://e209d09f-5af8-48a0-acfc-72d03e9bea0d.filesusr.com/ugd/946fcc_9c420166c130437c88a96f81410ce1c7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vatosolikijike/20068841653.pdfIn PDF document text
    • http://guxejusoselota.myartsonline.com/sowima.pdfIn PDF document text
    • https://5fa60de5-32ab-41ac-ba65-77330e21e623.filesusr.com/ugd/2e16aa_0d0580c27c224210be26d727bf5c3f19.pdf?index=trueIn PDF document text
    • http://jafixomedimun.onlinewebshop.net/gabaxujoxivaruwewadeja.pdfIn PDF document text
    • https://s3.amazonaws.com/votawawo/attraction_movie_in_tamil.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_off0000ed51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED51 5224 bytes
SHA-256: 0c361e332c25e408cca618a34f643274d777265573617408ec4dcbaa932f109c
font_01_sfnt_off0000ff1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1A 11164 bytes
SHA-256: 00e94ed16a5efbc844d9643da3de134c47a212de2b2dafd053258a6df45cf76c