Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff98b26894c63814…

MALICIOUS

PDF

83.2 KB Created: 2021-09-01 16:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 15de0689be9586f81da50ab23adc158d SHA-1: 1eb51ccbeab3e3aedbdcd88371b3eb0a68ecdf95 SHA-256: ff98b26894c638144380304dcb6740e9389e9fe963eb3292b9dfe39d0ec843ab
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document functions as a link farm, containing numerous embedded URLs that point to compromised websites and potentially malicious content. The primary purpose appears to be directing users to external, untrusted resources, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://inwebjor.ru/uplcv?utm_term=unsweetened+applesauce+healthy
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/c247fdd424b9eb014de812548f0082ee/21199828160.pdf
    • http://jubileejec.com/userfiles/files/37362457525.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7752e2d944---38102572132.pdf
    • http://southeastern61.com/clients/0/07/0748cf78e2268043913ae7c14e09e996/File/govuk.pdf
    • http://stauarchitetti.eu/userfiles/files/10917142920.pdf
    • http://flatadministration.com/uploades/fckeditorfile/26982090696.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7507a378b---nilamovivakonozi.pdf
    • http://degrossier.nl/uploads/file/17277365836.pdf
    • http://yuanjiangchem.com/upload/files/14632769600.pdf
    • https://civilkontroll.hu/uploads/file/55687183100.pdf
    • https://finatwork.com/userfiles/file/95090486560.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161182d2e66efd---9636418405.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/jbc0q77uecatgqr21e2s2vgaru/69035134888.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607edc6a931dc---98635863089.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16129807fd32f1---7782035818.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160beb7ff1e884---revowiropafesebokor.pdf
    • https://fengshan-zhennangong.org/upload/ckfinder/files/turisewata.pdf
    • http://vhz.cz/user-files/75214407719.pdf
    • http://scandirent-new.ru/uploads/assets/file/kavul.pdf
    • http://jd6618.com/jd6618/file/2021-8/file/LwpCms2021_08_30_07_49_11_2391.pdf
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e27336cbc---nuwotowoduvesuti.pdf
    • 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_off0000dec4.bin
115a1dd1c325f3e72f73ae802e2f000987b6381fbe75b123e2a386f044f65bc4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC4 10608 bytes
font_01_sfnt_off0000f707.bin
489b4d77ef42aecd57e63c112e7eb22cc852a7aa9f5bdae10e7fe598723bd71e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF707 18308 bytes
font_02_sfnt_off0001265c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1265C 16792 bytes