Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf9b50884f2517d0…

MALICIOUS

PDF

87.0 KB Created: 2021-07-02 00:00:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e529c462aa8dbc0f10049139cd143cea SHA-1: 8f34feaa5b6d8df8334fd99cade9063d0e347b04 SHA-256: cf9b50884f2517d0a79ab8adf2eb9bbaeb819abeee4aa21eb263218fce7b68d7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised WordPress sites. This suggests the document is designed to act as a link farm, potentially redirecting users to malicious content or phishing sites. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.
  • 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://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/9c2b1879bf95896659a755727ae57c45/88602091772.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/672ce3425e30878148964bde3bce7439/xuvupufowag.pdf
    • http://vuason.vn/upload/files/7475011405.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608420d25a270---pifegexinudaw.pdf
    • https://hgb.se/filer/file/78416891559.pdf
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/35545527843.pdf
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/f54a1fb0793152e91e306e96a21b6f65/83639075943.pdf
    • http://extracam.es/app/webroot/arxius/file/91378605191.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160749666d09bc---bidarevexi.pdf
    • https://cristalensi.com/public/File/15045269816.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160857b370b7dc---watedoxewubow.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608742a91f6f1---pinudusekidow.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd408dd2a7---34677252715.pdf
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/r5sf750kes2uq9lemn4f1t2285/jekoforosumixovuvanular.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160989f27cbe7e---kapuruzuvijebetifuxowu.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/a2d4b647097c51549d71275c0c1c74bb/ruzixapunibimawap.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1608e504b47ede---91489795731.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160802da307616---7697188727.pdf
    • http://abovomedia.hu/_user/file/29070962255.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa64f8c859a---gugoru.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/bns9pgetaobaqihpkakf925ikm/bonedowaben.pdf
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16087dba40747d---76843774280.pdf
    • http://mackyz7automotive.com/js/upload/files/51087347651.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e03d5c4de---xawexoraramuzigizogo.pdf
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/c4b55bc818539703719cac461ff2f2ce/senibobitamobasozi.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=early+stage+abscess+in+mouth+cheek
    • 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_off0000f0d3.bin
ba8e3e76aa0a77ed76616654371eea667361f8d44aec8578d643f0a5a7c041d0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D3 11108 bytes
font_01_sfnt_off00010a8d.bin
1dcf2fa84cc90a38a768c40c99c46c50454fa1e176a85054c5127fa2f86275fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A8D 16908 bytes
font_02_sfnt_off000136bd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x136BD 16792 bytes