Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4121e40b4038c87…

MALICIOUS

PDF

82.2 KB Created: 2021-09-03 23:02:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9dac543e450ff7916ef154cdcb17d923 SHA-1: 9d2ac1bf04090dd4b3d57b7b1fca22bc31801340 SHA-256: a4121e40b4038c877c5f6254af901748eb98b96d7ccfe9455bf4659c1e51960e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/jslur75rc9opkd59amqud10kq8/baruzipepafudavosa.pdf
    • http://bsp-oblspl.org/ckfinder/userfiles/files/somudamis.pdf
    • https://alamansyria.com/userfiles/file/riremoduso.pdf
    • http://dambi.pl/userfiles/file/29618622310.pdf
    • http://strelnicebudejovice.cz/userfiles/file/73607562742.pdf
    • https://familienarbeit3plus.ch/userfiles/files/nuwekotulimefijo.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/uuqocd0j3dhjtf4cjn75v4suce/tuxepozusijizizumajetejo.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4db67d9a2---97529114570.pdf
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/gunitomaralulanarezol.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c8dc6edd0---vinadarusogominu.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/46h4occ0oer7f49rv65geejj82/depejapininulodepu.pdf
    • https://boyanbolyarski.com/userfiles/file/67150451559.pdf
    • http://munsusa.org/userfiles/file/20210609090623.pdf
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/domomuruparafixigimotif.pdf
    • http://asiancfea.org/userfiles/file/neregezawisatapeba.pdf
    • https://candica.pl/ckfinder/userfiles/files/54228032361.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160828157d73d8---xixafizizinizufojija.pdf
    • https://xn--80aggmy8c6c.net/UserFiles/File/tidelojuboj.pdf
    • http://jacsonsfurniture.com/userfiles/file/60172618122.pdf
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/xelatororuzaduwod.pdf
    • https://gtselect.fr/ckfinder/userfiles/files/64355764158.pdf
    • http://everest-c.ru/ckfinder/userfiles/files/voketonilafajig.pdf
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/nupuwidajuvuleneso.pdf
    • http://klwas.org/userfiles/images/file/91555335489.pdf
    • https://motelandratecuci.ro/userfiles/file/2593098329.pdf
    • http://helpibr.org/clients/f/fe/feaff840d005acecac0f151e8679c8db/File/bidorezanalilegake.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=lego+worksheets+for+preschoolers
    • 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_off0000db16.bin
f1544f35be64884464ea6ac8623137d542b95c68275e94e8cebf941dc53629ee
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB16 17992 bytes
font_01_sfnt_off0001099e.bin
a09c7e30b959daee520333ab9c7b11988a2be26c27ee8a4b1b46a1a170ea3b8b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1099E 10536 bytes
font_02_sfnt_off000121db.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121DB 16792 bytes