Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0cf6a527685b083…

MALICIOUS

PDF

82.0 KB Created: 2021-09-24 12:36:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a67fa0c0dc762ab4f44a73ff9e61107c SHA-1: 3aeff56cfb16b2b0768cb1fdf60f7acb2b3f5f82 SHA-256: f0cf6a527685b0839a1b0892c33bedf55fa91f9f701f857396092ca7b3a19a35
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the nature of the embedded URLs and the link farm heuristic strongly suggest a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://ketchas.ru/uplcv?utm_term=nanka+mel+punjabi+movie PDF link annotation
    • http://munnarinfo.in/userfiles/file/7705304441.pdfIn PDF document text
    • http://finpacecuador.com/userfiles/file/23492498138.pdfIn PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/tusoz.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/gorenunifuxijak.pdfIn PDF document text
    • https://economiadecomunion.com/ckfinder/userfiles/files/pijitibilidipuf.pdfIn PDF document text
    • http://vce34.ru/attachments/file/70053966581.pdfIn PDF document text
    • https://yasacompany.com/upload/files/muzebotunijoguvutibububo.pdfIn PDF document text
    • http://dhf-china.com/d/files/lefejidatizotibepebaxakoj.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/xerazujizikadilukexovipi.pdfIn PDF document text
    • http://ginkgokatsudb.com/uploads/files/falifomase.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/bucfhbgdrd9bj8dbq8jhulj2is/purazokutof.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/39628372695.pdfIn PDF document text
    • http://www.recko.ru/ckfinder/userfiles/files/xeremojevedojadejezo.pdfIn PDF document text
    • http://pibar.tw/uploads/files/202109071509257380.pdfIn PDF document text
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/sesawul.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/luvazobetek.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/bisutisulo.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/zikunoramiliz.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/90115360241.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/28670657351.pdfIn PDF document text
    • https://allcondosales.rodeodrivecondosale.com/userfiles/files/97081134249.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://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_off0000da77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA77 18564 bytes
SHA-256: 63684b889351348da6ebe3413db58503d18d2f0938436180a1ec19aeeff4902a
font_01_sfnt_off00010af0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012307.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12307 10552 bytes
SHA-256: 4d96a20105f6d1d61333ae193f003c786fd1ce2b8ca22ea04eedc9cd527b156f