Malicious PDF — malware analysis report

Static analysis result for SHA-256 23a3f8f9961cf4f1…

MALICIOUS

PDF

131.8 KB Created: 2021-09-21 09:50:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d72d9d4fc8c8566df453f794b8847632 SHA-1: 2c548b502feeae8d42e752643488c19c2f0187e5 SHA-256: 23a3f8f9961cf4f19956546562ae8cc6e0f5816ade564ac6504f9a0459b90046
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicating a pattern of using multiple distinct hosts for redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure points to a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9898

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://le383.com/uploads/files/vigagegaxenemosesu.pdf In PDF document text
    • http://alrabbancapital.com/file/files/purilusolutuzedemoluw.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/wurapujevod.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/wixivoma.pdfIn PDF document text
    • http://www.sunriseacademy.in/ckfinder/userfiles/files/47761125227.pdfIn PDF document text
    • http://serviceelectric.ca/userfiles/file/33402265631.pdfIn PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/wedironipiwivokuwikafim.pdfIn PDF document text
    • https://excore.hu/ckfinder/userfiles/files/55577469734.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/sefabigafarapanu.pdfIn PDF document text
    • https://narellesastro.com/userfiles/files/27337140936.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/2e58357a9f7fdd5734275a61eba9ed1b/26693499686.pdfIn PDF document text
    • http://integrotech.eu/zdjecia/file/59882353255.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/91297370760.pdfIn PDF document text
    • http://househouse.it/userfiles/files/65938967320.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/12054619794.pdfIn PDF document text
    • https://asesoriagade.com/app/webroot/files/files/3482209866.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/39397834863.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/xawava.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/jebuboxesipazexabi.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/39637045679.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/6cf3df5a7f8c9f9dd624d441681246b1/vunopajafap.pdfIn PDF document text
    • https://altaitur.com/ckfinder/userfiles/files/87265749920.pdfIn PDF document text
    • http://dailynewsodia.com/assets/ckfinder/core/connector/php/uploads/files/31710202736.pdfIn PDF document text
    • http://nikkenj.com/userfiles/file/8059451350.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=llano+en+llamas+pdfPDF 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://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_off0001a1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A1C2 21432 bytes
SHA-256: 66bea67a81bece62f509b27c896cc8b6de2eb955ba83f9b187ee5a0981522eab
font_01_sfnt_off0001d7b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D7B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001efcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EFCF 10324 bytes
SHA-256: dc69644cc20dc349815f769cb12339f74b2942943e5e546d813df8d7f0ef37f0