Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9f48d6781be0768…

MALICIOUS

PDF

71.4 KB Created: 2021-10-03 19:23:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 391d70061aea8d552f5bb37af60098eb SHA-1: 0947ed2d2040410147370e5b2cd691be089fe1d0 SHA-256: f9f48d6781be07688b0870dca04bc0ec3a388f93bb55f6899e9ff6797a4b29d3
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a malicious intent to redirect users. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely a phishing or malware distribution lure. No scripts were extracted, but the structure and URL patterns are consistent with a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gmt-tw.com/app/webroot/userfiles/files/xikonarirogarox.pdf In PDF document text
    • http://www.deep2001.com/images/library/File/10321597663.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16131d4accf793---77790958682.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/fdc39b0ac00cbae824d5495f5d5506a0/34938564466.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/57469200102.pdfIn PDF document text
    • http://hainfelderteich.at/wutigudeveguxitudobifux.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/pabipal.pdfIn PDF document text
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/tetorovebukekumimizijamij.pdfIn PDF document text
    • http://seattlebestteriyaki.com/uploads/files/66355078279.pdfIn PDF document text
    • https://em.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/84899935437.pdfIn PDF document text
    • http://webspace.mysdam.net/images/newsletter/files/97177490784.pdfIn PDF document text
    • http://stefani.cz/fck/file/93607329206.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/47621477500.pdfIn PDF document text
    • https://ecosolar-energy.com/piceditor/file/75231464029.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613fbe19aeb73---buwesubaxawa.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/29615113668.pdfIn PDF document text
    • http://bisenzia.it/userfiles/files/nolojuwavitufeva.pdfIn PDF document text
    • http://nfc.soo.jp/file/lokesowivegewez.pdfIn PDF document text
    • http://flexinform.com/hirlevel/file/41684669130.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/sejevuke.pdfIn PDF document text
    • http://senkyu.jp/webroot/img/files/barokoximol.pdfIn PDF document text
    • http://associazionemillesogni.it/userfiles/files/38037078666.pdfIn PDF document text
    • http://abwjefferson.com/uploads/files/90062146564.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=monosodium+citrate+anhydrousPDF 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_off0000b2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C4 17384 bytes
SHA-256: 90cd25e896c8cc73f976b57ac2ff2d02ea9e8b05a3250c7b8e73249336e3229b
font_01_sfnt_off0000df33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74A 10796 bytes
SHA-256: e7d2b6d4bab8ac6f4ca6681b9059b940f63a962215fdba939ca03eaffd1c165c