Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac68893bc0371bc5…

MALICIOUS

PDF

81.8 KB Created: 2021-09-21 19:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 85448d51f95f8fd2988140ffda5d9c27 SHA-1: d0fcb37aa852a16095f8e7625539f10bf832d175 SHA-256: ac68893bc0371bc52f89bd5f4dcce8e1810e47253ff5011c8ecf48b730e003e8
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous unknown URLs suggests an attempt to distribute or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://francoisdaulte.com/ckfinder/userfiles/files/fepaxekugugasefekufevo.pdf In PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/78354209336.pdfIn PDF document text
    • http://elfast.ru/userfiles/file/89932217306.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/55763540638.pdfIn PDF document text
    • https://kuraniterbiye.com/resimler/files/12082510837.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161444e24bac58---11180980127.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/semulawazu.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/10407571125.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/petifike.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/64248816641.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/gikem.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161301c241a7f9---dexepotuneliwubevu.pdfIn PDF document text
    • https://bangvetthuong.com/luutru/files/12658909506.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/kikepuw.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/38025448520.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/39735742874.pdfIn PDF document text
    • https://0286869143.com/editor_images/files/83943341699.pdfIn PDF document text
    • https://bda.ch/ckfinder/userfiles/files/kesodesemozaninenozi.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/jibemusasesigofiguneburi.pdfIn PDF document text
    • http://daehwa.info/uploaded/file/93833340766.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16145daf74e0c0---povatibegalipu.pdfIn PDF document text
    • https://zbmbudomont.pl/userfiles/file/gotudejufixirufobazamawu.pdfIn PDF document text
    • https://glozor.com/userfiles/file/95690523266.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/23311591653.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/40494912648.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+delete+a+copied+link+on+androidPDF 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_off0000daeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF302 10508 bytes
SHA-256: c68ccdaa87feed58764d03e9faadd981d3124d82af98839616262d0825cc95ff
font_02_sfnt_off00010afe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AFE 17928 bytes
SHA-256: 60e58fffa9f57bf841baea2cce1cb5580b21369c3e621af7f183e5d922fd801d