Malicious PDF — malware analysis report

Static analysis result for SHA-256 77d33e2f73ba737b…

MALICIOUS

PDF

74.8 KB Created: 2021-09-03 03:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f0dfc421156a8425f0bef3a2c48224b5 SHA-1: edca6ea1dd425874f586dadbadd8092affcf7680 SHA-256: 77d33e2f73ba737b46e3cc09b4bafac45c7de02a1cd0fda2c4a8160fd6305edf
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads, suggesting a link farm designed to distribute malicious content or manipulate search engine results. The presence of multiple unknown URLs indicates a potential for hosting further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16096a09bbab63---47390407722.pdf In PDF document text
    • http://ritadas.in/userfiles/file/daxatatovupoz.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/4441017450.pdfIn PDF document text
    • http://mtsp.by/userfiles/files/98955392415.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/8777577267.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/mujizapavojej.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16082b8d6db874---jasugudadabew.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/sinosut.pdfIn PDF document text
    • http://opusincertum.it/userfiles/files/xukesivegagufiwivem.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210718/file/16265706424782.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/mebiwojedigulob.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/e8183d3176938b4709271b89c7b155a3/42496407883.pdfIn PDF document text
    • http://a1climbing.com/userfiles/files/4995462482.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073ed943a0d1---jugovoxudagobuloxa.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f27cbe81b0---9952828760.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/5625902557.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/noberuzomifevupazinu.pdfIn PDF document text
    • http://webhenevents.com/clients/868374/File/dimijuzelotipo.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf3fa400a1---39425711636.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/51720748373.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/17156492625.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa86f181a4e---tetapa.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/zapexat.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed82579eb82---kavejovujojegekilabipav.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/c59b75bbbb467e329fbc436cc3858700/18343924010.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=free+math+worksheets+for+8+year+oldsPDF 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_off0000c117.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC117 16560 bytes
SHA-256: 200f4b9c5dfb9f845ea8c674dfd0b8309fdeef1b35aff600b9c21f517263a47e
font_01_sfnt_off0000ec1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1E 10900 bytes
SHA-256: 323c7948ba1c1fc24b5fbb8314485d3bd72cab272e78ad77f1e04d9ae74ba6ed
font_02_sfnt_off0001057c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1057C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1