Malicious PDF — malware analysis report

Static analysis result for SHA-256 aff22f441b276888…

MALICIOUS

PDF

78.7 KB Created: 2021-09-09 15:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 451255c36ef2bd4ec9825ef77ce3f7ee SHA-1: 881bdb221ac5ec072470a74c5bad69c4b8deb889 SHA-256: aff22f441b276888f1a8d2f4b43f7e5f7a95de6cb026cb54ad8f4d55cff49a51
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains embedded JavaScript and a link farm that points to multiple distinct hosts, including compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of embedded JavaScript indicates potential for further malicious actions beyond simple redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://ccskin.com/geektic/files/dovapolewomemuki.pdf In PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/2148916266.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/mewosikani.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/nusanupelodixi.pdfIn PDF document text
    • https://anjingliar.com/contents/files/6918422281.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/50166877274.pdfIn PDF document text
    • https://europawindow.com/app/webroot/img/main_content/files/pirirutuze.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/xusofejapafebezefa.pdfIn PDF document text
    • http://darangyi.com/userData/board/file/34249840118.pdfIn PDF document text
    • http://timnhanhonline.net/upload/files/butumolemasolupagafew.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/ed62cc955a539d8649eafbc1df896880/pepijajamupudoje.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/18647399926.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f731e1e8e1---zivilifupazibo.pdfIn PDF document text
    • http://www.ville-civaux.fr/admin/js/ckfinder/userfiles/files/69095798703.pdfIn PDF document text
    • https://www.emcp-pmce.ca/_includes/ckfinder/userfiles/files/notegugubujelazojaki.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132df3a145b2---39989304977.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/a4abd4e1e5106feab81c3cfe5f1a154d/67292340132.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=drag+racing+club+wars+modPDF link annotation
    • 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_off0000cd56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD56 10808 bytes
SHA-256: 027339f0243ee55369d5d7e098419e22a06d7774b0d81c12ec6a6bcf0ca378f6
font_01_sfnt_off0000e5ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FF 18500 bytes
SHA-256: b73ed4296f9786457797409aad0985794db1dcbfa0d31882c2021afeb6b00d76
font_02_sfnt_off000115e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1