Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b55c5573af0c00d…

MALICIOUS

PDF

84.4 KB Created: 2021-07-04 18:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b811d13b5b067806e5ef6a21541ff889 SHA-1: b0a08e5febecb6eb841419b7a0ed9379bdadb441 SHA-256: 0b55c5573af0c00db27491dcd5653f5ef34d8dc3bfe43dc51d0ca763720c859a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting it functions as a link farm. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate an attempt to redirect users to potentially harmful content, possibly for phishing or malware distribution. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://lncxjzxxw.com/upload_fck/file/2021-6-18/20210618072713264718.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098c85202457---7354218297.pdf
    • http://anhopphat.com/uploads/files/rokofilusadavezawivudire.pdf
    • https://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/46d39f872556e113398715e26423a68c/68851353635.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/24e527639a9a4be18506e26273fb0d2e/lobotoz.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/6118c0486effc8902dd79e8727211e31/diravafakexapinobomuki.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1b5e9a230---somet.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/a1082580a25d10937b4312739ed7fb10/kumaxajolu.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/jqfcv3dkg55s7i9gc7ee92rb7t/51913202193.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c828079600---90687367376.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/ek1a3rs90u7nc31m4chpns61a3/49433914706.pdf
    • http://cbgnfinance.com/userfiles/file/daketobalepigo.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b894665950d---jafasulapekuj.pdf
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707c6e4b07b---virevufogotujuguna.pdf
    • http://ahsaipu.com/v15/Upload/file/20215735838994.pdf
    • http://abacusnancy.com/userfiles/file/repabutatutigivij.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46227d4552---susuzalitasiwolik.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac71e44358---3194901865.pdf
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/90bafbafed607e81447e23a9eea2ef46/xevakekagirinowaredono.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30991704eb---9682536425.pdf
    • http://emeraldcovepartners.com/_data/images/file/fukadebenakezegonitubewa.pdf
    • https://heatingboiler.ca/fck_upload/file/90890994619.pdf
    • http://cissi.it/userfiles/files/58485599902.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=laser+treatment+for+baby+birthmarks
    • 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_off0000e85e.bin
ff76d2a5988a8c6667544c400a2255ebbd39dc5a5b9221d735f7ba39d1c5229f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE85E 16828 bytes
font_01_sfnt_off000113e2.bin
26e5aab393ae71c2d2492d62825c96ce0e27083bb0c5f3ee866d73d770d16f7a
pdf-font-stream PDF embedded font (sfnt) at offset 0x113E2 10736 bytes
font_02_sfnt_off00012c6e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C6E 16792 bytes