Malicious PDF — malware analysis report

Static analysis result for SHA-256 8640043a6ad81740…

MALICIOUS

PDF

89.9 KB Created: 2021-06-29 18:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e3a7821ed5fa6562ca59b0a9e1e90068 SHA-1: 75c63e5bf6253059d1d616584fbdca2940504198 SHA-256: 8640043a6ad8174000caecd5b11dfc0f35b9dd09d7199b02a27a44884f204547
156 Risk Score

Malware Insights

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

The PDF file contains a large number of links pointing to various compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple compromised upload links and a link farm on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9883

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://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/7d42b7299e6e6a8a044f7979755d3639/39370718345.pdf In PDF document text
    • https://alteanetworks.fr/img/file/bazawaxipusanotusaniveto.pdfIn PDF document text
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160876fe2f2c17---78551646108.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/1auu36sniu34arna7vvotlk18p/rezepenodegatevuvu.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092f6bd8dcad---70896734358.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b9d097090---89753343667.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160762516c18a6---93373792113.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/000c2edb925837b14b6c50474fd677fa/zekolaxavasesiniwirotijo.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/20219b8a453ad4ebb5e72981c79d2baf/mowajonuzoxiwuwom.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/widekobajagawi.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/ri00dbicafvos5q1l6os9b25t0/56550407772.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b868ab52e45---87346688741.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/59134770179.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/71722929857.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec4d8063c6---roloperu.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607302b2075f4---40213699237.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/65341200493.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/15959430713.pdfIn PDF document text
    • http://bbbswalkforkids.com/clients/c/cf/cf8d0549bdc9bbdffca8bc0db9808b96/File/13536375236.pdfIn PDF document text
    • http://impressivetravelvietnam.com/upload/files/komajebebo.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/86036208027.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f5f1af037---fatonaguberusumojiwodax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=demon+slayer+dubbed+in+englishPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB7 10952 bytes
SHA-256: bfcb651fb84dab7b2124c822d7969eb5df1159f34c9943424181ecf0a35bdfff
font_01_sfnt_off0001059d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1059D 2464 bytes
SHA-256: cfd15d66d9f898d74d6647a227608bf93a07aecb9783198ff7ad6f283d6a2ff0
font_02_sfnt_off00011063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11063 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00012875.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12875 18800 bytes
SHA-256: 078d31f2135cffb075c55695856c812d317d32a8ac120e936d68fa263cd671b3