Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e882a61c410bcc4…

MALICIOUS

PDF

89.1 KB Created: 2021-06-27 09:26:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e4537f18a32cae44bb8ea9b11bc2d2e0 SHA-1: a8cf8cc64db12ae69780b35fec240df11b866427 SHA-256: 9e882a61c410bcc467884be324053e457c1135406c909a6828503d9705a731c3
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress upload directories, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV also flagged this file as malicious, specifically as a phishing trojan. The embedded URLs are likely used to redirect users to malicious sites for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b3dd74d5589---48650600629.pdf In PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/l4l1bvp9lq04spauhdag1jgk1c/gubupejotig.pdfIn PDF document text
    • http://wjvanderheidedienstverlening.nl/uploads/file/nofotunutilerenod.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/e40ea076a5a0e7513eaed69b4ce27647/wesomulitadefepup.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/nowixawimazi.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/34460944050.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/0e4163e04fa74d7380729fa8d834b440/77884867495.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d721681ef4---65549470973.pdfIn PDF document text
    • http://muskogeeroughers1967.com/clients/9/98/9899c641331876fb313f08ec475a0443/File/mopizudulep.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/relopodivepazefe.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/ea26c978cf5399925ac36b18bf9ff271/60331699107.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8f5bec2bc---faxuxufitilu.pdfIn PDF document text
    • http://londonjip.com/userData/board/file/3135733582.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/9b0c8dec2bc5690bd664d688e26aca96/12404026102.pdfIn PDF document text
    • http://alisawedding.com/upload/users/files/65046790724.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/jaradiwifubevusur.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/72937154843.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16096e2b5723e1---dumibilafiv.pdfIn PDF document text
    • https://unosms.us/userfiles/file/90356758329.pdfIn PDF document text
    • http://mosjob.ru/images/file/rivegigazorubo.pdfIn PDF document text
    • http://jmestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vofazudonarolilafid.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3955195430786691dae3b729727c10f7/kekotarigulitizurej.pdfIn PDF document text
    • https://agrimal.pl/userfiles/file/zujetasil.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2165ec813---36667252766.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/68bsut9eatf18bp6ftl3efgf8s/dakorut.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/2fa989c40021be175df4ddaf1aecba81/27820206247.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+long+to+get+a+bachelor%27s+degree+after+getting+an+associate%27s+degreePDF 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_off0000f5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010e02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E02 16936 bytes
SHA-256: c2df84f5114fbbe7fa6d467284607ed4f909206c94be34f82b01bd94c649e668
font_02_sfnt_off00013a5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A5C 11008 bytes
SHA-256: ffe2ac531ab0fe27adc838353d789814598f4887d297561073267f90d1033c41