Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc77761e22544d0c…

MALICIOUS

PDF

83.7 KB Created: 2021-10-06 06:16:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8e3f23b851136f975466b2a01085971d SHA-1: 49cd7338c5b0965af75645449c5b9ffb371bf857 SHA-256: dc77761e22544d0ca11a3c54155c9705973ec77de5664654d6e28be8163f8b3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised WordPress upload storage or appear to be disposable. The presence of external URIs and link farm heuristics suggests the document is designed to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pistant.ru/uplcv?utm_term=how+to+find+the+equation+of+a+line+with+the+gradient+and+y+intercept PDF link annotation
    • http://thietbiotovn.com/Images_upload/files/23614064928.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc37a294f7---36567313265.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/gijuketonomig.pdfIn PDF document text
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/funigeligebizogemo.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/bigemuvuled.pdfIn PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/lanusenuratolopidufaki.pdfIn PDF document text
    • http://kelkenaghshband.com/app/webroot/img/files/vabixogowokexowo.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/64802440976.pdfIn PDF document text
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/20924423547.pdfIn PDF document text
    • https://maturana.cl/upload/file/dapolel.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/09e81b149a9830ef2b809269bbc1fc61/84955918474.pdfIn PDF document text
    • http://abbeytraining.net/userfiles/file/20343959646.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/46941957897.pdfIn PDF document text
    • https://kuepancong.com/contents/files/nefatazukenojuse.pdfIn PDF document text
    • https://coevent.ru/upload/files/jazuwetuxufovozasurav.pdfIn PDF document text
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/81922386757.pdfIn PDF document text
    • http://gavinlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/10425909653.pdfIn PDF document text
    • http://archifolder.com/userfiles/files/jozogelubonuneloloremu.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1615165edc078d---konoxotufatavazede.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/watolusup.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/filuvebojali.pdfIn PDF document text
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/mumofunot.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/82532774628.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_off0000dbc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBC0 19436 bytes
SHA-256: f375f3f0fd310c0936e6fac1e401fae16c661529d931fc31c56265be702eb5c0
font_01_sfnt_off00010ec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000126dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126DC 11168 bytes
SHA-256: 63f314cdc283f5dff6272af1a7579945b164af4f2a8cf133e5187a1b7d401c5f