Malicious PDF — malware analysis report

Static analysis result for SHA-256 d59b1a744e280dbb…

MALICIOUS

PDF

82.8 KB Created: 2021-07-14 04:05:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 645e364f7bc5cfe4fceb9ed09b054e96 SHA-1: 1994166e8506bddca6b6652fb344b3ddb98e8a72 SHA-256: d59b1a744e280dbb451113f9f4391766ff0f9d19c424037a8e4cf6655d7e24c3
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to compromised WordPress sites, which in turn host other PDF files. This structure suggests a link farm designed to distribute malicious content, likely for phishing or malware delivery. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160729d10dbc06---54785425523.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a06fbceb8---27203405048.pdf
    • http://hieuchuan.com/upload/files/93387194368.pdf
    • http://wildpflanzen-planung.de/file/22119668834.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/6o015b51r269j2gp61leadjvej/45505532275.pdf
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/8af5370310bad4c717c6e6c383df190c/detopoporimanolurugugek.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806d4e93820---31841071277.pdf
    • http://www.deco-interieure.com/userfiles/file/45008784972.pdf
    • https://aawyx.com/sites/default/imageuser/file/93548658436.pdf
    • https://koffiewarenhuis.nl/app/webroot/files/userfiles/files/20882073394.pdf
    • https://alatheir.com/atheirwsfiles/file/gezid.pdf
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/8rbqi23srg6eg5pkl7p2q1vph7/53627832162.pdf
    • http://asiadomainstore.com/userfiles/file/87753946710.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb4438987f2---jakojasemozolovenixik.pdf
    • http://zhxndl.com/uploadfiles/files/66803542465.pdf
    • http://yummyschool.com/_UploadFile/Images/file/20051424658.pdf
    • https://art4you.sk/editor_uploads/system/files/negividiriseniku.pdf
    • https://longhoang.vn/upload/files/67109971692.pdf
    • http://vandientuchinhhang.com/upload/files/godetelapivujokiw.pdf
    • https://brs.jo/userfiles/files/28646559269.pdf
    • http://aire-limpio.com/img/editor/file/piregunojoworejew.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/112shgsrclu476lvvjla90m8ku/93542258963.pdf
    • https://qualitymattressfactory.com/admin/userfiles/file/40294246466.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=private+account+viewer+free
    • 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_off0000e218.bin
398bb07997b228e53d50945a29b8c66a7958b906c7763c054141976e72ca037c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE218 17036 bytes
font_01_sfnt_off00010e9d.bin
b3e70ca33b344b184c6d9813207c3ad52509a3691428fe2b7a4b2470e090b398
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E9D 10368 bytes
font_02_sfnt_off00012643.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12643 16792 bytes