Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c684eedc25150c…

MALICIOUS

PDF

100.4 KB Created: 2021-07-01 20:20:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: a7e84e4cff03b89d790ee150c1d87ff8 SHA-1: 113a81d74f89d3e1947c88addc37de88e4018bc3 SHA-256: b5c684eedc25150cb90a6cec8e93abe3971d765937a29515239c2caca1373d57
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to numerous external URLs, many hosted on compromised WordPress sites, indicating a likely phishing or redirection campaign. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://coiffurenais.com/userfiles/file/jonasiku.pdf In PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4990936170---47480019773.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16075e2c515cfc---zitusarubivedobisipa.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/ludefaluzajaw.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aafbb26efc8---vasofipesujetizutigok.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/c77d1f046b3b6e7cc649fddabaccc849/febil.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/64804313490.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803c72ac24a---zulasenisuralufikenobesa.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/8q4k8neq5srtuc8ktl1h9ng8j6/vikevefeperefodukig.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba8253c6f3---48909815679.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/gedolaravumoxamok.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a7144668970---46234078497.pdfIn PDF document text
    • http://pizzeriadevita.it/userfiles/files/84567523558.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/q0pags5937668fph02ubs0l7h7/digaxuwitawuwotemof.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/vinerasar.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/c65db22d400971058d9c6c486c5ad564/75438105196.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/jomimikifutuxadid.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/82500927157.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/639474a1a20d66382ac8e8c776398b1f/70261936038.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/piponugofevupef.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609db526e5dff---14840785022.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc431f3fc2---30351750897.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=need+for+speed+the+run+manualPDF 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_off00012429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12429 10748 bytes
SHA-256: 8c2695c4d25743eaa0f995e5d4492a05e99d7a934ef6b23616819766130c5300
font_01_sfnt_off00013cae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CAE 18220 bytes
SHA-256: c570b5604acff9fd39d53cbe19017bae3cdb3982c093d51caedc79ae7eee0542
font_02_sfnt_off00016c84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C84 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1