Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdd9d77ad718f87b…

MALICIOUS

PDF

96.4 KB Created: 2021-09-15 14:12:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d30799f8f5be6010c2b7874c907f0524 SHA-1: caf3b9776c0eeec30f38afd4092810f7a3009db3 SHA-256: cdd9d77ad718f87bca24d4b93b5b1f96408039d3fd7a48a069e616a33789d105
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, with one specifically identified as part of a link farm on disposable hosting, suggesting a phishing or malware distribution lure. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques commonly used for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://crewmak.ru/uplcv?utm_term=the+road+to+oxiana+pdf PDF link annotation
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/6675ef736e77b35d74102ac492a3526c/73728948283.pdfIn PDF document text
    • http://kovovyroba-nosniky.cz/UserFiles/File/65952244365.pdfIn PDF document text
    • https://klcmekatronik.com/ckfinder/userfiles/files/92540389862.pdfIn PDF document text
    • https://shevian.com/images/file/2925353260.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/55657829051.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/53471289392.pdfIn PDF document text
    • http://topstec.com/d/files/pozeratixoruno.pdfIn PDF document text
    • http://pscemetery.com/userfiles/file/mekobunidi.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/gunobevolotasiwex.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/jogogukixujixiwunujunogu.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/vejid.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/27163573292.pdfIn PDF document text
    • https://sadex.pl/fck/file/69903462588.pdfIn PDF document text
    • http://weilandensemble.nl/ckfinder/userfiles/files/84525202646.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/37414362563.pdfIn PDF document text
    • https://maggievanostrand.com/uploads/media/file/fowosusomipu.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/29793856175.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/42593332712.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133be478543f---78573213652.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/mixonifebe.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/mutelimofadesalipanu.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16316919283035.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/76416393503.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/soporedesoganovumizij.pdfIn PDF document text
    • http://meta-min.com/files/rapibilabogofumexufobafa.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_off00011460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11460 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012c77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C77 10444 bytes
SHA-256: 6d97f2f2748ba98714cfc07c4a5e9915d03dab5a716044809036afbf665d0ff2
font_02_sfnt_off00014414.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14414 18320 bytes
SHA-256: aa1a22967df76f7ef77732ddb4e08144077bd6c0980a818c7477d603fddff278