Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e663d1fa4f92165…

MALICIOUS

PDF

70.0 KB Created: 2021-09-27 10:10:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5eb2c1406f0aa10bd2d5f9465b32bb58 SHA-1: f151233740852a29b711a75c4938fa7652a9d55f SHA-256: 5e663d1fa4f92165aecc08cb7c7d55a2235b2e76af3b2c1f03c9d1c41bcde167
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised websites or disposable hosting. One URL specifically points to a PDF file hosted on a compromised WordPress upload directory, suggesting a potential distribution point for further 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 http://ebbers-schilderwerken.nl/uploads/files/52911399232.pdf
    • http://thepokeluau.com/uploads/files/tujukewifisukawiwiji.pdf
    • https://rockyhotelsgroup.com/uploaded/files/bisinigijeruj.pdf
    • https://jungleflightchiangmai.jungle-flight.com/Uploads/files/86884023617.pdf
    • http://teewer.mn/ckfinder/userfiles/files/jekukudodi.pdf
    • http://zzquansu.cn/d/files/ruvolawize.pdf
    • http://abwingssuffolk2.com/uploads/files/dilafejode.pdf
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e4f60e6e8b---43017139969.pdf
    • https://pensiuneavalentina.ro/app/webroot/file/gugulutosifedisetedet.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1614dfd3b7c6d3---30354338904.pdf
    • http://omonetach.pl/foto/ilustracje/file/xixexugo.pdf
    • https://fertilizerproductionprocess.com/d/files/rupopivejo.pdf
    • https://laflammerouge.ch/userfiles/files/85742742468.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/72acb8230d5132fcd5624658dcf376ea/76946803350.pdf
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/37054012255.pdf
    • http://nbc.ua/design/pic/file/88940593141.pdf
    • http://e-motyle.natura2000.pl/imgturysta/files/40452174364.pdf
    • http://georgekoldun.com/var/upload/file/wetabodew.pdf
    • http://mywayrtk.info/userfiles/file/20064484210.pdf
    • http://shengnabei.com/uploadfile/file///2021092712355286.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/34822785236.pdf
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/2799568705.pdf
    • http://goddesshair.net/upload/users/files/28577020390.pdf
    • http://eur-idea.com/userfiles/file/84376909192.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=barclays+stockbrokers+app+for+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b133.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB133 16792 bytes
font_01_sfnt_off0000c945.bin
8943a4874df05c21bcb5e4e6ffb1ad8dacb1f53af63e1bf2d00390416c749638
pdf-font-stream PDF embedded font (sfnt) at offset 0xC945 14980 bytes
font_02_sfnt_off0000ee79.bin
c9c3ddc0d09805970f91e467b5819c060b93dc137f3bb29b6adb03e7c0452a4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE79 11012 bytes