Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaa492a6460535c8…

MALICIOUS

PDF

83.9 KB Created: 2021-09-23 19:44:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9695eda42b401ea9099e37e985c64029 SHA-1: 1bdc38f4ac407de8e690ece0909a79d2a925a65c SHA-256: aaa492a6460535c809d8dc4cf6ee819c16b4e6327efab549b45c7169b22f75be
176 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to various domains, some of which are hosted on compromised CMS platforms or disposable hosting. The document's structure and embedded URLs suggest an attempt to trick users into clicking malicious links, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://ylwlgwadmin.ylwl.cn/upload/files/82983869502.pdf
    • http://bestorkate.com/uploads/ckeditor/files/waxamefi.pdf
    • http://tajeer.co/userfiles/file/15860116319.pdf
    • http://dh-cell.net/ckfinder/userfiles/files/86286310664.pdf
    • http://colegiosantarosa.com/uploads/imagem/file/wiminusugenusodadegasiga.pdf
    • http://al-bandak.com/userfiles/file/butekol.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/45e4e6ca1f6ea8544ab4403bfe105d59/55675896919.pdf
    • http://sjar-tech.com/uploadfile/file///2021091005043696.pdf
    • https://gaziemirkentkonseyi.com/upload/files/50781921162.pdf
    • http://gsxr.hu/userfiles/file/suvawitilolifimiv.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/d585781494053d0c00b355e2ddd4a03a/kezijor.pdf
    • http://resetimpianti.it/reset/public/file/pukuvisarovenumubujadusok.pdf
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1614bc05b09b3e---nunusom.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/2b16298lgfe4n2oavk7gffrph6/1833903439.pdf
    • http://wellfoto.cz/pictures/files/jenozofiridanedokodu.pdf
    • http://sushinamu.com/uploads/files/zelan.pdf
    • http://studioagm.it/userfiles/files/28677180853.pdf
    • http://kledingindex.nl/images/uploads/11174237038.pdf
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/juzupemog.pdf
    • http://asremajazi.com/uploads/files/98765735942.pdf
    • http://gruaszarate.com/ckfinder/userfiles/files/liliwolela.pdf
    • http://mfahk.com/upload/files/90729142531.pdf
    • http://paraglider24.de/pics/fotos/1/file/dowatenoxakidilunibaweluv.pdf
    • http://formpart.com/upload/ckfinder/files/42239442157.pdf
    • http://podwierzba.eu/ckfinder/userfiles/files/75123166416.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=qr+code+scan+android+studio
    • 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_off0000e436.bin
7f581e6e6db49501453ce01733b70718c7a51b39fb7ab7078d04004b584ce685
pdf-font-stream PDF embedded font (sfnt) at offset 0xE436 10476 bytes
font_01_sfnt_off0000fc36.bin
d9ed3ddb69deff098de3ef663274e3d6e3b0495f67b3ddf5145092b061086d96
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC36 17812 bytes
font_02_sfnt_off00012a3a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A3A 16792 bytes