Malicious PDF — malware analysis report

Static analysis result for SHA-256 33a2609d7f4d53ea…

MALICIOUS

PDF

81.2 KB Created: 2021-09-09 17:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4593989c6189d9c2c49a7985b06c193a SHA-1: 232cf6a1dad26df0b8027d6184ab55ab0bda9934 SHA-256: 33a2609d7f4d53ea0dfd0251014fb81849da5715a4a9e9b22c67825e3a80793e
126 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. The PDF contains numerous embedded URLs pointing to various domains, suggesting an attempt to lure users to potentially malicious or phishing websites. The 'wkhtmltopdf' authoring application and the structure of the embedded links, including UTM parameters, are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://er-trans.com/img/produkty/files/81917276353.pdf In PDF document text
    • http://duquenne-moteurs.fr/webroot/upload/files/wuzomiriloxujokipabubiviw.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/vumalejuge.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/zuzugewaboju.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/gutasosifus.pdfIn PDF document text
    • http://kantipursecurity.com/userfiles/file/tejijunamixupunise.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/furuwabinuxudoluwemenaf.pdfIn PDF document text
    • https://vilnius.cvzona.lt/resources/img/files/duboxufiw.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/ritaxuberuforero.pdfIn PDF document text
    • https://3rproject.eu/ckfinder/userfiles/files/demudorenedimud.pdfIn PDF document text
    • https://frutalmente.pt/site/upload/file/70703929095.pdfIn PDF document text
    • http://whuntex.info/userfiles/file/79356062728.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/xeridemukuwanoxugovep.pdfIn PDF document text
    • https://www.gico.ge/ckfinder/userfiles/files/jegazeraputemabixixudow.pdfIn PDF document text
    • http://www.saletime.gr/admin/fckfiles/file/3293586301.pdfIn PDF document text
    • https://delcinfo.ru/img/files/files/vulugabomubipirukajek.pdfIn PDF document text
    • https://accidentmatters.com/ckfinder/userfiles/files/11461959846.pdfIn PDF document text
    • http://ladyvenus.it/userfiles/files/84587775167.pdfIn PDF document text
    • https://kibledergisi.net/resimler/files/muguwokivuzekot.pdfIn PDF document text
    • https://demetraproject.eu/ckfinder/userfiles/files/nulagazivomipar.pdfIn PDF document text
    • http://branpc.in/ckfinder/userfiles/files/sagebepuxarubof.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e53f96578---nudakurexikudofizepemut.pdfIn PDF document text
    • http://eng.sut.ac.th/tce/2016/administrator/ckfinder/userfiles/files/fabus.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/72972025188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=stick+shadow+war+fight+apk+modPDF 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_off0000d67a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67A 17972 bytes
SHA-256: f6eb0e4e3af1f18e53d6fe494b1cdd06dd0a5c6112deecd2a43296bdbca098c4
font_01_sfnt_off000105a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A3 11040 bytes
SHA-256: b7b95652e57adba04fbe7dd341e0c2e9e8b28381e4a275974b939a4204a547a4
font_02_sfnt_off00011f36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1