Malicious PDF — malware analysis report

Static analysis result for SHA-256 6169e78923714c43…

MALICIOUS

PDF

82.9 KB Created: 2021-04-05 05:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 868d2478068d9d3a2d8dd57191e8d77c SHA-1: 8d6e9af4c01b734ff511eaa75c2eb48f098db3d7 SHA-256: 6169e78923714c43cc5fb010892b2c061cc54746c68a4c6dec77aa4bf2307733
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links to other PDF documents hosted on various disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The embedded URLs and the nature of the link farm point towards a tactic to manipulate search engine results or lure users to malicious content.

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://baarspo.ru/award?keyword=candidiasis+tratamiento+hombre+pdf PDF link annotation
    • http://wunedefewadonif.22web.org/fundamental_of_aquatic_ecology.pdfIn PDF document text
    • http://mufajaku.medianewsonline.com/rejofadekewo.pdfIn PDF document text
    • https://musekakilex.weebly.com/uploads/1/3/1/4/131406804/vawosatasoxaz-pudakubi-siruwunadabaw-jalagomegiwo.pdfIn PDF document text
    • http://polobasopika.mywebcommunity.org/how_to_unclog_a_badger_500_garbage_disposal.pdfIn PDF document text
    • http://sifaritube.sportsontheweb.net/achenbach_test.pdfIn PDF document text
    • https://dobuxodujunov.weebly.com/uploads/1/3/2/7/132741154/ridumigabe.pdfIn PDF document text
    • http://rafupofamurawaf.mygamesonline.org/7563057283.pdfIn PDF document text
    • https://vusuranozaxo.weebly.com/uploads/1/3/4/0/134012668/gekofewadamu.pdfIn PDF document text
    • http://roxedizusugu.mywebcommunity.org/mesanebolag.pdfIn PDF document text
    • http://nokunejojepeje.22web.org/a_ha_take_on_me_piano.pdfIn PDF document text
    • https://tozilamuvopodes.weebly.com/uploads/1/3/5/9/135966944/31b60ae.pdfIn PDF document text
    • https://wavupuzubeje.weebly.com/uploads/1/3/4/2/134235525/duselos_lezisus_vomoberotutalu_loperozop.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://keregimuw.onlinewebshop.net/boccherini_minuet.pdfIn PDF document text
    • https://c3e810f9-371e-40b9-9a0b-4695a496ec77.filesusr.com/ugd/2c7c49_749b2563bae041b5a134b28f31ff75a0.pdf?index=trueIn PDF document text
    • http://budokukikaririd.rf.gd/nefuzuluvatifotolebu.pdfIn PDF document text
    • https://4cd5a77a-be8d-44ba-8952-4177873115c4.filesusr.com/ugd/930050_9f50c09c52a94dffbdc9351da793e9ef.pdf?index=trueIn PDF document text
    • https://d3919fa5-c020-464c-a773-72e456e10464.filesusr.com/ugd/29136f_bfea674e9c5b42d5bdf624f19cc23bac.pdf?index=trueIn PDF document text
    • https://81866859-049a-499f-9904-b5dd27b5453f.filesusr.com/ugd/84a5c6_d7fa908cddbd4e16829599924aeb8fad.pdf?index=trueIn PDF document text
    • https://d38713d8-f9e0-49bf-8e72-3f46774ce551.filesusr.com/ugd/b3faf5_f80acd2922944d99856b988a8b9f88a4.pdf?index=trueIn PDF document text
    • https://e5b7f393-9b83-42c5-a877-5b85c0c772c8.filesusr.com/ugd/77b42d_9af46f47334c402d937cf0525b73177f.pdf?index=trueIn PDF document text
    • https://31e64076-56b3-4e53-9780-179364fbad2f.filesusr.com/ugd/d8d3cb_c3a7550710004441af9349460f53cbad.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010471.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10471 5296 bytes
SHA-256: 2600e14a637eb18c33b2cc3763bb40abbb50593971ab7d44fba12f2a864fe213
font_01_sfnt_off0001163c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163C 11852 bytes
SHA-256: f4d9de729a7ee0d701268205e41f84c5193cd4e3f01dd731ca25034d159a6567