Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a3080f5cda5e498…

MALICIOUS

PDF

82.2 KB Created: 2021-09-10 22:11:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5fc44747e543bd78144ec06de6cd3a0e SHA-1: 00dd3d58eaa6e8b4d2830efa009388b66d6e64a7 SHA-256: 1a3080f5cda5e498a0b67ac9a9e2c0832c373f415d90126ebd5ce46c6bdde516
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with numerous URLs pointing to disposable hosting and compromised CMS upload storage. These findings suggest the document's primary purpose is to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://synerhu.ru/uplcv?utm_term=how+to+use+voice+commands+on+android PDF link annotation
    • http://suvagcentr.ru/userfiles/files/55770438861.pdfIn PDF document text
    • http://tplustech.com/images/ckeditor/files/6946712356.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613496e1d9d10---matifawo.pdfIn PDF document text
    • http://spprp.pl/userfiles/file/vuvixidevibituja.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342243f37b6---bevut.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/41550482208.pdfIn PDF document text
    • http://air-ned.com/uploads/files/53942334306.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f42852ccbf---tuzigugifodofibet.pdfIn PDF document text
    • http://ilkemymm.com/image/files/35301205396.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/72893637539.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/46547491774808d0e534b4acab94a3aa/tisekenafowukunela.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/bilon.pdfIn PDF document text
    • http://ducnhua.com/upload/files/31768693326.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/sosepimogisikurezetep.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/41376591433.pdfIn PDF document text
    • http://lorichphoto.com/pictures/file/rixoxirejidoselibidep.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/15250501983.pdfIn PDF document text
    • http://art-wonders.com/ckeditor/ckfinder/core/connector/php/uploads/files/sasiri.pdfIn PDF document text
    • http://barexkft.hu/userfiles/file/33292356375.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/52653223483.pdfIn PDF document text
    • http://ucokampen.com/media/files/fowaputoxapamuke.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/rozim.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/miluw.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_off0000dc5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5E 10728 bytes
SHA-256: 3865cdae15f1872f4ab93b64e6d9d89912cbf5476c863cb1c18b2af3f174c3ef
font_01_sfnt_off0000f508.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF508 18228 bytes
SHA-256: b97d8f20ffd5fe4367c5c67ff77bf36a8c0c01bd69f946458cfd1154914b5661
font_02_sfnt_off00012362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12362 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1