Malicious PDF — malware analysis report

Static analysis result for SHA-256 c18f13fe1707eca9…

MALICIOUS

PDF

82.8 KB Created: 2021-08-13 15:25:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 379f0d34ae28bbfa2907a7f0ff8f99fd SHA-1: 808d0e5fe00a21024c737ec171cc1fce9014b463 SHA-256: c18f13fe1707eca9007de9a95ba4ef3ca5f7cb294fc502ce8c54547f37a5d1ca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs that form a link farm, likely intended to redirect users to malicious sites for phishing or malware delivery. Heuristics indicate the PDF is part of a link farm on disposable hosting and points to compromised WordPress upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://chcial.ru/uplcv?utm_term=how+to+replace+a+maytag+performa+dryer+belt PDF link annotation
    • http://nsdadventist.org/FCKData/file/7836999636.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c564791925c---xukalezako.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/88570865978.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072e6a2d0676---38530605828.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/xeterape.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160861871073c7---1747009358.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/8t2a9osvja2hb25mtggvrm62de/xitopagisuwum.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/janorozewed.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096f2727a27c---teges.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/bibifisemaz.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/86965459926.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/11086858367.pdfIn PDF document text
    • http://thuaphatlailongthanh.com/upload/contentFile/minhchau/file/82204239380.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/xitilefozarejivijaw.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/24692882350.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/2r9148ogss2a4hbb1q87cvcjr2/jiwovivorekusezekidelosim.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2fba5190e---tekenaxusogatibisilu.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/notagetemigidof.pdfIn PDF document text
    • http://siltherm.com/ckfinder/userfiles/files/solotafisopida.pdfIn PDF document text
    • https://markeishahall.com/wp-content/plugins/super-forms/uploads/php/files/7261fde6d4bf3f3c1b4bf1c96f7a3e22/61192894470.pdfIn PDF document text
    • http://thedreaminitiative.org/Content/Admin/uploads/files/58800594431.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077bdf86ca74---domeruvawopajiroradunusi.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7a678f5b0---58449944372.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/7254824298f43b6f08ef0c5a682dccc7/nurixurosidad.pdfIn PDF document text
    • https://livres-arts.com/ckfinder/userfiles/files/bikuxirovanajuvededipe.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/8f4697221a2b4ef0a9b079c575078e1b/saverotexo.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_off0000e1d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E8 15888 bytes
SHA-256: 979ce66a32c05eee0455db834a9610ccc72ec3db5f66d50a8cc829b322f00fa9
font_02_sfnt_off00012305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12305 10932 bytes
SHA-256: 079c69993a038489c68d0509aa7529e53d82ac81110e1db332373552d57bc1db