Malicious PDF — malware analysis report

Static analysis result for SHA-256 25f81206831fb27a…

MALICIOUS

PDF

91.0 KB Created: 2021-07-13 20:01:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 075e19c6875a9d843950c11497f45329 SHA-1: e8ccad22e603714ef4c6adc1749ea85f0c05eb8c SHA-256: 25f81206831fb27aaf0effbdfad7e4caaa69d2024850bfb4d71f5535798e3677
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The document body is unreadable, but the heuristic firings strongly suggest a phishing or malware distribution attempt via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/tvfj9kekmeqrq84e1c37pjjnot/pavutejusufonanatasimawef.pdf
    • http://texmet.pl/userimages/file/towelebewewukidofulewabu.pdf
    • https://virtualpulse.eu/UserFiles/file/nenadililovisojevifeb.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160cb495fb374c---40217386184.pdf
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/nedanojoxa.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/88fc2997d176485f80cc715bfef8cee4/dadafotexeruzu.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c79fa4d71a8---31622736110.pdf
    • http://jimmartinfamilyreunion.com/clients/35696/File/sifukuregalo.pdf
    • https://kidneystonetreatment.in/userfiles/files/80551961618.pdf
    • http://www.tobywells.org/media/fckdir/file/69045443306.pdf
    • http://ballstonfamilymedicine.com/clients/861402/File/wofulofisinetanoki.pdf
    • https://cortopolis.ar/userfiles/file/zomeruzaxugukizomisetu.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160979c4f88c61---mexagutalubolavi.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609b89af4ae9e---93493780859.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/18112aba33a235bd52ef3deff68fbc9c/19599582347.pdf
    • http://psmpetcare.com/clients/76030/File/37831923706.pdf
    • http://sarljarry.fr/userfiles/file/82737743840.pdf
    • http://www.deep2001.com/images/library/File/sasazatakuzuf.pdf
    • http://amon-syotengai.com/userfiles/file/59270508285.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c01e16541c8---gugobivapipinex.pdf
    • http://parejalecaros.com/adjunto/upload/fck/files/31842946456.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c72e800335b---vatunokanufojet.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/a5cm6qa7g4tk58vfds8co7i9e5/xinit.pdf
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/f4f6adf29a7a49ffa31d68fd3dc9386f/53371548582.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160787fbf73f31---susofafolaruwevig.pdf
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc33b4e251e---77285788241.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=word+study+games
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010349.bin
4d0232800cdc6ebc0da4f534c03e514b31caaa454fb07a49686900fe7880ce4c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10349 10556 bytes
font_01_sfnt_off00011b44.bin
dc36299c7e7d6cb12e41835876836093f5b48ccb3a00c81a1dff8ea61d9479e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B44 16792 bytes
font_02_sfnt_off000146d1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x146D1 16792 bytes