Malicious PDF — malware analysis report

Static analysis result for SHA-256 defa08acf5f048ac…

MALICIOUS

PDF

74.2 KB Created: 2021-09-19 09:09:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e9be9a0753775058678950738f9aa8fd SHA-1: 95e76868d1bfa17140fd9ae0e409a34c54af01ab SHA-256: defa08acf5f048ac71e437cb584c935bf2026d5a7fc6223d9248f8307001aedd
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's designed as a link farm, likely to distribute malicious content or phish users. The embedded URLs, despite some being marked benign, point towards a network of potentially compromised or malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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 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 http://cen7dias.es/userfiles/files/78163565052.pdf In PDF document text
    • http://olech-rzeszow.pl/userfiles/file/bitekefazakobugufufov.pdfIn PDF document text
    • http://onroerendgoedindex.nl/images/uploads/ximerisakesig.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/36852597146.pdfIn PDF document text
    • https://pratham.one/file/69704133499.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/7516246782.pdfIn PDF document text
    • https://zhansq.cn/upload/file/nipedufabanaponowobonuso.pdfIn PDF document text
    • http://escrima-rlp.de/userfiles/file/66081810083.pdfIn PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/zeguredenewubeduxiratitag.pdfIn PDF document text
    • https://sandipkumardutta.com/ckfinder/userfiles/files/8130055748.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/54989443768.pdfIn PDF document text
    • http://jolanyee.com/upload/files/202109120251374677.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/debunelaxug.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/4827348034.pdfIn PDF document text
    • http://modaxch.com/userfiles/files/33319792843.pdfIn PDF document text
    • http://gdlianyu.com/uploadfiles/file/3705785590.pdfIn PDF document text
    • https://plagij.at/ckfinder/userfiles/files/68237268529.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413ef155cf7---tojifovakolisipuposoti.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/7602976082.pdfIn PDF document text
    • https://coherence.cz/userfiles/file/31310658136.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/xatanopofowawewisegit.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/pefuwatajubowixexurivin.pdfIn PDF document text
    • https://medgal.pl/admin/ckfinder/userfiles/files/7512691951.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=watch+munna+bhai+mbbs+onlinePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c04a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC04A 16604 bytes
SHA-256: 55190db6934f9304827d5d1dd188657bf150d0319be37cd563c2ff64c630a69a
font_01_sfnt_off0000eafb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAFB 10628 bytes
SHA-256: 0f355b39e4a14455627d6da345b78a93c640cc531bb21b894871d96a46d6d79b
font_02_sfnt_off00010330.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10330 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1