Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab672cfdc356c5f1…

MALICIOUS

PDF

85.0 KB Created: 2021-06-15 16:57:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 8850410d02fc78aadc140bceecc7123a SHA-1: 99e0dc03a23354155b60a55c3bc7625b5e82b54a SHA-256: ab672cfdc356c5f110bbae07f0c631c78d28f88e5a572120ebe246eea0ef42d0
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to external resources, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious sites or download further payloads. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://philabc.ru/uplcv?utm_term=photo+outline+maker PDF link annotation
    • https://wodepcb.cn/uploadfiles/files/96680514664.pdfIn PDF document text
    • http://clubselectionvoyages.com/images/file/rudivujolulipulevibir.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5caa9e4c4b---wamonutepixesasubo.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609431c75595d---15124165600.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/wokefifetomedudunaxusem.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/15480419766094cf39b6c60.pdfIn PDF document text
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/02668782777ca03819e92afbe019f4d3/tupolozogosogelov.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/68963572510.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/wenaxevukoxudaxaxaladapa.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16073682299eba---56780731383.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-6-5/20210605035441163897.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/3288026645.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16096fb77c1d01---24407506291.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/40aefd9403170752520be18a187a7562/jivek.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/d452f8244e6aebcd04ba61a599706ea4/bepewunetuxogodit.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/9f25dae32b1615153cc6cb127825df15/sezutexusukewegusinufudef.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000110b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B0 4812 bytes
SHA-256: 1858637ee21b8a839aaee8150220587377089f3d5a936c2e3831ef0379d5816f
font_01_sfnt_off000120de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DE 11176 bytes
SHA-256: 172d2ae33234fbac84625bf4b2f1386fe2e4301031ddbfe9fe6aeefa9e73e949