Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c77d76fbb2f857…

MALICIOUS

PDF

85.2 KB Created: 2021-08-31 19:58:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5685037692d7152ff23c67f63f343d39 SHA-1: 2c99d99a53a9b903b7a2f8f680fc6112a351fe89 SHA-256: 31c77d76fbb2f8570c63cf6470e32eeb228de4ecf7584b16db628841eb6ccac4
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to multiple external URLs hosted on compromised CMS uploads and disposable domains. The presence of numerous links and the use of UTM parameters suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160cb8be01f5dc---wuxupetek.pdf In PDF document text
    • http://fecirturizm.com/resimler/files/goniwo.pdfIn PDF document text
    • http://0965818789.com/CKEdit/upload/files/xunilekevevisegedani.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/zumotugawalabilolabuj.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/c794be313683e9e8be1a6f0348f134c5/bazapodukigapemobirivi.pdfIn PDF document text
    • http://murzilka.biz/images/uploads/file/dabibu.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/muviranu.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160fed0fdda5b1---50065019310.pdfIn PDF document text
    • http://sdds.be/userfiles/file/75921168162.pdfIn PDF document text
    • http://armanetti.com/images/36592549492.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160baf6d420137---vinebupiluxudepisul.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/aeitb4h0psre431mqjitkqgkp6/benoronodor.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/nanena.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/6aefc861e2a172e838143ef0bc038d83/tewuvokamubebadufed.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb987231b8---81986370057.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/kirijufuriguxofevuj.pdfIn PDF document text
    • https://hijaustabilo.com/contents//files/kozawadututaxabe.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160bb52d464fd0---pavivelox.pdfIn PDF document text
    • http://voyagevietnamlaos.com/hinhanh/file/11326373015.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/24268c3971ef2470e6fb42f07439179b/puvaxosan.pdfIn PDF document text
    • https://indiantalentjunction.com/milan/media/nemazo.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f0c576928---53390755113.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/pobuderekokosenaxigobafa.pdfIn PDF document text
    • http://borisovhlebprom.by/var/upload/file/gusupezofamojexigok.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/lidevatizoragebiser.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=the+one+man+showPDF 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_off0000e7d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D7 10084 bytes
SHA-256: 3f2f16d14d13a2c36daeffbbefbf41e3e465aaf8f138a6f723fd0e02a41cfb96
font_01_sfnt_off0000fe2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2D 19144 bytes
SHA-256: cb070ab5633c1f23575600f67a8cc2be73476e13d51cb6c31469fffa3ead0917
font_02_sfnt_off00012f6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1