Malicious PDF — malware analysis report

Static analysis result for SHA-256 21001574d8858edc…

MALICIOUS

PDF

71.3 KB Created: 2021-09-06 04:34:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 283756b68230d3004208ccf301b5098d SHA-1: 1cc015ad298c068ac844e0462e00885c7bfc662b SHA-256: 21001574d8858edcc6c9e54e76d7874e5601b98376a507648fae85e12aeb747a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous other PDF files hosted on compromised websites, indicating a potential SEO manipulation or content distribution scheme. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple links to potentially compromised CMS upload directories suggests a coordinated effort to host and distribute malicious or deceptive content. No scripts were extracted, but the structure and URL patterns are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/1a4c0426b49ac3bded1a7963660c8bb3/batuvanukiwepexofajobiwi.pdf In PDF document text
    • https://parfumzone.ro/files/file/54046260084.pdfIn PDF document text
    • https://zhavezbozi.cz/data/file/nakobasobo.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/4b1a0b56f84c91df71e8d177037ba3f0/11985006795.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/rekukotagetoregexuf.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/b6jc7f0s618fp0ve3afk25sotg/2148054762.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ac114bf36d8---34958333374.pdfIn PDF document text
    • http://rasciindia.com/firetech/ckupload/files/23705396256.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/8952c9136aa4054ccaadb6acee218e8d/ragunem.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1607291679fda1---1377546212.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/89244357232.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/10839513958.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/a9fe99e498524909ee4d2fa462ef6069/6444430842.pdfIn PDF document text
    • http://pjzhengwang.com/upload/file/20210721_151419_168.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b683a9c19cc---bepigogufobafawuwalixuvam.pdfIn PDF document text
    • http://centonze-vini.com/userfiles/files/20733440627.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f03e8ce3042---75514383399.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/dedibagitefobu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dff8b3c440---wuvomunanozexu.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7960491075---bumetotolir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=medical+dictionary+pdf+2018PDF 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_off0000b65c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB65C 15792 bytes
SHA-256: ac7d805b4b87e2c8ff5d989675d8c96178dfffea168d367a38780df3b4c7df82
font_01_sfnt_off0000dd9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B3 11056 bytes
SHA-256: a55c0946662e7f690e23357712a1f1db2e00abeae6307c5e3e6e3993ed443d2b