Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad2557bfd7f57127…

MALICIOUS

PDF

71.5 KB Created: 2021-09-11 13:49:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: aa828539d9018fb13333a708c289026c SHA-1: 3f26cd3bfc37f88e654177e4043ea385d477a81a SHA-256: ad2557bfd7f57127fe56363bb2dc67f8b7abce17704d541aae8350d2b71f7212
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=free+unused+xbox+live+codes PDF link annotation
    • https://tahuacoop.com/cms_gpadmin2015/sgi_userfiles/userfiles/files/sonomevonujuz.pdfIn PDF document text
    • http://dekobonner.de/userfiles/file/bejep.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdc03c2f2c---43040355614.pdfIn PDF document text
    • http://jogagongu.pl/userfiles/file/jewamakabeximuluguwasu.pdfIn PDF document text
    • https://khmernative-rice.com/userfiles/file/fesataruv.pdfIn PDF document text
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/81936498885.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/71726040100.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/44546641527.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/37746757628.pdfIn PDF document text
    • http://hidramaco.com/files/files/48596114689.pdfIn PDF document text
    • https://dermatologie-chamonix.com/userfiles/file/finobozenuvewofagineb.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/54087507541.pdfIn PDF document text
    • http://atek-ent.com/upload/file/gowefasibade.pdfIn PDF document text
    • https://kamionosnyelvlecke.hu/userfiles/file/bitomagusirigizadano.pdfIn PDF document text
    • https://kontiko.com/ktkweb3/images/upload/files/repodewenex.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///tepemeril.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0f08d235d---50597061492.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a3cec2db3---87516007917.pdfIn PDF document text
    • http://ttlh.vn/storage/ckfinder/files/64860076405.pdfIn PDF document text
    • http://feminella.ro/upload/fck/diwoman.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ec6671913---mamikuv.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/jatasafumuluxi.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/60587380025.pdfIn PDF document text
    • http://taihegas.com/filespath/files/20210910010203.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b5fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5FE 10488 bytes
SHA-256: 37fb66dd0322e3ff6e45e8dd80318ef7cea2ba9fad76d96d439479f6cfb5987e
font_01_sfnt_off0000cdee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDEE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e600.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE600 16712 bytes
SHA-256: 85db3ec3bd2a4ed12231834d58eb9d4da4396650671706442790617a524c9461