Malicious PDF — malware analysis report

Static analysis result for SHA-256 8db34ed323296122…

MALICIOUS

PDF

87.6 KB Created: 2021-09-23 09:38:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 436495b3ffb4f754694247f506a7ceb5 SHA-1: ba3579de6825632b9122377b88ee40e21adeebe5 SHA-256: 8db34ed3232961225dc535747a88b0769d01670ed7c3360f857a31f3424850aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and the ML_NYX_PDF_MALICIOUS firing strongly support a phishing or malicious content delivery attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://locktactyuma.com/ckfinder/userfiles/files/dixepoxikotefuladevi.pdf In PDF document text
    • http://sochisushi.nl/survey/userfiles/files/37729193311.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__613B0D8916EA7.pdfIn PDF document text
    • http://krakowska98.com/zdjecia/fck/file/75684961996.pdfIn PDF document text
    • http://aqcorth.specialty-match.com/upload/files/71934761211.pdfIn PDF document text
    • http://ingegneriarossi.it/userfiles/files/18186652653.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/73672513845.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/74740116970.pdfIn PDF document text
    • http://maychebiengoduykhuong.com/media/ftp/file/besubomemobepemejela.pdfIn PDF document text
    • https://bi-kiesabbau.de/cmsimple/images/file/6231661356.pdfIn PDF document text
    • http://teakdeck.pl/files/file/bajewilusavufiz.pdfIn PDF document text
    • https://bongkartuantakur.com/contents/files/xizowujiti.pdfIn PDF document text
    • https://www.sophrologue-nimes.fr/upload/news/files/96643341243.pdfIn PDF document text
    • http://kibbkw.com/uploads/files/93311852429.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/85334019013.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/f5accb7a9c261f56acdd849af882ba4d/94324292842.pdfIn PDF document text
    • http://morethancars.nl/uploads/edytor/file/1306740103.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146e2223de0d---35544677111.pdfIn PDF document text
    • http://jutaek.humenia.com/upload/userfiles/2021/09/files/210909124428.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/xakuva.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/bagoporaxus.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/fobadumuzezovizo.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/naxazinalokekidut.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161423cb73994e---60583645258.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=free+download+ebook+intelligent+systems+a+modern+approachPDF 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_off0000e99f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE99F 11372 bytes
SHA-256: a089e2bef89f01ef9c9f2d3103b7cd221cc89ac3fcde4fef1f1f533be1c73381
font_01_sfnt_off000103d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BEA 19832 bytes
SHA-256: 0793d1510fb11eff5dfdea233df905bfbf9a1d7c21c41d5596ad28ddbf9a4653