Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9a00db2d76377f1…

MALICIOUS

PDF

91.2 KB Created: 2021-07-07 22:35:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: fbf3a131b9758a406f8d87bbae8d2b6a SHA-1: 13756be1e979c5d02e658ed70cb3cd22e3109f62 SHA-256: b9a00db2d76377f1b8a2dd956ed49857de119c1b3f3e22d2d158d3aab7eee675
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, directing to numerous distinct hosts, many of which are compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The embedded URLs and the nature of the heuristics strongly suggest this document is designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/f74c263471405ad40fafabccf17e6cbd/8741313059.pdf In PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c12fbe72b91---dikozavupusuxemopu.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/65722067262.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/79091584152.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607864bdb2de9---40001071674.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/a773d47e9bd004913121bc82fce8de5e/bofomuzogulamiruz.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d51a3c99b99---nevupujizopotux.pdfIn PDF document text
    • http://wannawwannie.pl/userfiles/file/7352979757.pdfIn PDF document text
    • http://a-mega.ua/images/uploads/file/29499410871.pdfIn PDF document text
    • http://anupbolivia.com/images/files/vogowokeniw.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/91fb74267cdde1cecda526560fac89f1/7543948246.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/gipezezavolakaf.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/zigeloximowukum.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/ac15afd119cb1f378b94270ed4ecd720/buladofomogu.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160df30f15fc63---bilawugavaduzakojesesose.pdfIn PDF document text
    • http://benhvienlaptop.biz/userfiles/file/9837569496.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/70233713428.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/dejev.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/7id0g1fhrkqodkb0eo4tr5a3pc/38955482974.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608280e950fb7---xokab.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb79b173aa---gewibemutulinexak.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/6386805f24d7a9c807ac0ad006f96121/marozogezosobila.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/eb95c764cb375bef19f45acb21db8bef/gawaxasi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=assessee+under+income+tax+act+1961PDF 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_off00010073.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10073 17484 bytes
SHA-256: 04676e40a1de1d70915ec4b84315849bda06901c07ee328086f4dc599ba1ac48
font_01_sfnt_off00012e65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E65 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001467c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1467C 11056 bytes
SHA-256: 9b2c62a3e9585bdf321638b3fabbd345a1a4e48c0eae47ce471efffd6bae80c0