Malicious PDF — malware analysis report

Static analysis result for SHA-256 def27b813bd4750e…

MALICIOUS

PDF

84.2 KB Created: 2021-05-02 08:28:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 062d97b9ff319e4777bd6cdb9cac92c2 SHA-1: 4a092c0c62f19d80a7d7ba3a8c1ffb5723a7272a SHA-256: def27b813bd4750e94fb56d72219b8dd3070e94072f1052ebd373c50a2dff4cd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS upload directories, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7b3de4d50---todilid.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608239197d26f---31081601626.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1608461f66cec6---45966341659.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/dc816edf94ce850d39e9794117747f87/migugolawimugolatare.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4313ab7c6---64019037891.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1d23c891d---86974758534.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160739e362b956---ropulesogefupukibo.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608bd9555e9eb---niwivufemamarozasesipot.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160706017426fb---regul.pdf
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/440f38188ccb568b2372294d821a53ed/65517640754.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe9b1609f9---nerojuzivezasadisuviloju.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9cd6f3a95---99172645857.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb58f4d55e---todovazifamedesopuj.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/4cf5c30063f3594a0c52db3735d2d278/jokadowiturafenuvorejode.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d186f4b35b---99954365711.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=imperatives+worksheet+grade+2
    • 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://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe18.bin
d1972d38259f9dc2e541e24dff278317c1af3472734503115134b61bda718b9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE18 5308 bytes
font_01_sfnt_off00011032.bin
e6c64fa27b02fc7dd2c6bd3debc2a3e1227358f92b83fdbab5f63cdf873777cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x11032 11216 bytes
font_02_sfnt_off00013633.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x13633 4324 bytes