Malicious PDF — malware analysis report

Static analysis result for SHA-256 d91a8bf2ba3838f9…

MALICIOUS

PDF

70.4 KB Created: 2021-09-23 03:53:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a7026aa8cea1d146d69a11ae4b412210 SHA-1: 725d9049f9a4af7daae328e24a831b833f859588 SHA-256: d91a8bf2ba3838f953065adff0408e62951250d279ffb338cf5b575bdedd18f8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for Pdf.Phishing.Trojan and an ML classifier indicating maliciousness. The presence of numerous embedded URLs, many on disposable hosting and utilizing UTM parameters, strongly suggests a phishing or malware distribution campaign. The document body was unreadable, but the heuristic findings point to a malicious link farm designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=apk+hungry+shark+hack PDF link annotation
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/6617212863.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/dijizirasamubibawe.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/84490426550.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142951a0ee00---xeniwevobagom.pdfIn PDF document text
    • http://cosyromania.com/media/file/62070836313.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16132c88ab704d---13373951743.pdfIn PDF document text
    • https://ferest.ro/imagini_ws/sukuzasavopugakuwapowew.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/mutojikumusininekana.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/34921355412.pdfIn PDF document text
    • http://kmjmt.com/news/upload/file/210907072433863828gmo46y.pdfIn PDF document text
    • http://ipmarketing.net/FCKeditor/editor/filemanager/connectors/userfiles/file/bezifusidenalaxiveku.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/dasuvigokutakifepotegik.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/53995291979.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/95387799081.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/31796198967.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/todalufejasufebadixa.pdfIn PDF document text
    • https://pisausakti.com/contents/files/10650127128.pdfIn PDF document text
    • http://style4.allwebeasy.com/userfiles/files/14938604126.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/jasevumawipubodob.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/dibagugij.pdfIn PDF document text
    • https://bonvoyageindia.in/ckfinder/userfiles/files/xifefoti.pdfIn PDF document text
    • http://highgaincomposites.com/img/file/2021922165514.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16140e45b1d84e---12058121017.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/mixotesiwomiziba.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/jopidak.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_off0000b50e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB50E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD20 15528 bytes
SHA-256: 2c796ce9589764d8b952886e56b8f852fe96140907e7d734811b4ca1f5161355
font_02_sfnt_off0000f499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF499 10452 bytes
SHA-256: 79e5b1cb2b8770b469fa7af16a27bce74654c00649f7cbd0c2b95719575f41f1