Malicious PDF — malware analysis report

Static analysis result for SHA-256 3773f5af8ea63157…

MALICIOUS

PDF

70.0 KB Created: 2021-10-02 09:47:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f088e95a46f42612da75a5b06963a90b SHA-1: b147e4e5ed5911045e2945d14d89e1c02128e7df SHA-256: 3773f5af8ea6315766910db36c4c3026649e35811d54b24da051da48bb7c380c
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised CMS uploads and disposable hosting. These links likely serve as lures to trick users into visiting malicious sites, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://www.autoservis-hubatka.cz/admin/upload/ww/file/99081264889.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/aa9edc64951409d0223cd708744ed6a1/nulilajusonis.pdf
    • http://daehnfeldt.com/userfiles/file/98779453263.pdf
    • https://www.miotsukushi.or.jp/system/ckfinder/userfiles/files/88336789110.pdf
    • http://weingut-suppan.at/files/8384553999.pdf
    • http://supair-lux.hu/ckfinder/userfiles/files/wukevifazawapa.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161486bb276b32---sawagemu.pdf
    • https://senegal4d.com/contents/files/15805042168.pdf
    • http://sushi-belovo.ru/files/bolilojekaji.pdf
    • https://alternativecarrepair.nl/userfiles/file/81816818861.pdf
    • https://thic.muki001.com/plugin/ce1/ckfinder/userfiles/files/50602428193.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/7d14bd660bd61ef847fc1e049e72a449/43534170400.pdf
    • http://droneducational.com/admin/userfiles/file/mumozurowixobonetivegago.pdf
    • https://rimi.sk/userfiles/file/nefavip.pdf
    • http://labsshop.com/d/files/54848270324.pdf
    • http://realcomfort.ru/content/upload/file/17902445137.pdf
    • http://thelifelesson.net/home/tappingchanges/public_html/dowalumniusa/ckfinder/userfiles/files/virevasawano.pdf
    • http://soft-pro.hr/upload/datoteke/totupifajagozujuxosines.pdf
    • https://palcev.ru/userfiles/file/wirojewodowugema.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16157fd51782bc---636352479.pdf
    • http://angelcabrera.com/FCKfiles/file/23435749177.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16141b54922cea---sumekaropedefomuxidusaxij.pdf
    • http://orderbestwings.com/uploads/files/bakakixojafozino.pdf
    • https://siam-royal-view.ru/data/files/vekewiluwanidakubopapi.pdf
    • http://korsorlampang.net/user_img/files/mawuniwuvu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=swtor+sith+name+generator
    • 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_off0000b381.bin
2287eed44a4987b6a97ddecad50437e24d5864925fb013a0f0b9b4c0fccd3899
pdf-font-stream PDF embedded font (sfnt) at offset 0xB381 10668 bytes
font_01_sfnt_off0000cbd0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD0 16792 bytes
font_02_sfnt_off0000e3e2.bin
cb282bed1d4b2a4781c2b956a2b6eef9e4a212b63a8f91af5f9575233e7ccc60
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E2 15256 bytes