Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcbc588f6bb9c93e…

MALICIOUS

PDF

72.3 KB Created: 2021-09-27 14:50:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6f58dae54031185ac1bf7a86a392f330 SHA-1: 595812e02f4c1e18c5ee03be4ebebe092c90464f SHA-256: bcbc588f6bb9c93e09eb97c196fa825b5a64fe8095c94c5ebb4d1060a9a88fae
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links to external domains, many of which appear to be compromised or disposable hosting. The presence of ML_NYX_PDF_MALICIOUS and ClamAV detection, along with heuristics indicating random and link farm URLs, strongly suggests a malicious intent, likely phishing or malware distribution. The embedded JavaScript is a common method for initiating malicious actions within a PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=search+ranking+tracking+tool
    • http://csc0516.com/userfiles/file/20210911011107_gja0f2.pdf
    • http://www.shjkyq.com/up_files/FCK/file/55640058906.pdf
    • https://perfecthospital.net/FCKeditor/file/kumupafogulosili.pdf
    • http://precisao.net/files/files/76185442193.pdf
    • http://ourdesign.hk/ckfinder/userfiles/files/31418943166.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/u4d9dc58o0gb6lk60fa8htocjp/53247016540.pdf
    • http://ambulatorioveterinariovianello.eu/userfiles/files/82958483173.pdf
    • https://cottonweb.net/userfiles/file/wojazabi.pdf
    • http://luxcottage.ru/stroykamen/userfiles/file/danojafilalafi.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/rk5qjelas1ogr580bu0tqmtofr/25196353127.pdf
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/21016771336.pdf
    • https://olivierdaulte.com/ckfinder/userfiles/files/67682572510.pdf
    • https://kultmotor.hu/images/files/xaseg.pdf
    • http://valsadindustries.com/userfiles/file/57632924005.pdf
    • https://ksdc.in/userfiles/file/79773955982.pdf
    • https://mimpiindah168.com/contents/files/41448456299.pdf
    • http://hstairan.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/12297820293.pdf
    • http://artospace.com/pics/file/94468497432.pdf
    • http://polyalpan.hu/_user/file/ximil.pdf
    • http://tgroupsrl.com/userfiles/files/zajovisotudepuribosagaf.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16140cb86ca070---60385970349.pdf
    • https://aiaciran.org/cache/fck_files/file/vawakotafilefopibafotiwa.pdf
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/f41d2ae6b5a4e8e4d0ce5cc57f0cb401/vanuwejex.pdf
    • https://fontaine-eva.fr/userfiles/files/gibum.pdf
    • https://luiginoiobbi.com/userfiles/file/pilobesamisene.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_off0000b422.bin
fded06e2bd73226d585bb88b3bc40a7b7575ba9377939f71e3de70d3b67a9e5e
pdf-font-stream PDF embedded font (sfnt) at offset 0xB422 18028 bytes
font_01_sfnt_off0000e250.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE250 16792 bytes
font_02_sfnt_off0000fa67.bin
495682507ee1b7262f9cefbcf81c14a5d745abc3f38e5edf1ce68931bd6619cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA67 10508 bytes