Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7e345f8aad4489…

MALICIOUS

PDF

93.9 KB Created: 2021-02-16 04:37:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1a0b5595ee51e3b4db53e229d1758156 SHA-1: e94ff5c7990754e3d01de2339f2496a220300c10 SHA-256: bc7e345f8aad4489b0de520a683e17a4250b6329ba36b2e468218101ad33a2b3
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to other PDFs, suggesting a link farm or SEO poisoning tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://seumenha.ru/wix?keyword=hidden+figures+movie+math+worksheet
    • https://static.s123-cdn-static.com/uploads/4368770/normal_5fddd76f7acb9.pdf
    • https://bojowavezuzabi.weebly.com/uploads/1/3/1/3/131382797/rofedumuxapedojelag.pdf
    • https://cdn-cms.f-static.net/uploads/4386334/normal_5fe98a0ae0ab5.pdf
    • https://static.s123-cdn-static.com/uploads/4463272/normal_5fc64e8f6452e.pdf
    • https://cdn-cms.f-static.net/uploads/4470223/normal_60106ce0a7647.pdf
    • https://gugozakeku.weebly.com/uploads/1/3/4/5/134588211/8e546.pdf
    • http://gugaroro.iblogger.org/65227258952.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/kotenu/4974903966.pdf
    • https://s3.amazonaws.com/bubeto/fonobozif.pdf
    • https://s3.amazonaws.com/kovilowab/titozowevafofujusemu.pdf
    • https://s3.amazonaws.com/bidemewufa/chemdraw_ultra_12._0_free_serial_number.pdf
    • http://gisawuvuxe.rf.gd/pafedopogozogewibijazime.pdf
    • https://s3.amazonaws.com/dowavelaxam/4195648034.pdf
    • https://s3.amazonaws.com/xijuxosisomuna/89446461674.pdf
    • https://s3.amazonaws.com/rakabexozu/51982659956.pdf
    • http://pekuvem.epizy.com/bukiropadutozamubosuto.pdf
    • http://fuxazulofonu.epizy.com/burt_harding.pdf
    • http://pisumapopub.rf.gd/full_form_of_atmosphere.pdf
    • https://s3.amazonaws.com/davolazupivowi/mizefaf.pdf
    • http://punolubumima.epizy.com/birth_plan_template_nsw.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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000133d6.bin
5743d704bb52ed22bb34f3f9521126fe7882e10808812b47f6338223ae15c390
pdf-font-stream PDF embedded font (sfnt) at offset 0x133D6 5464 bytes
font_01_sfnt_off00014658.bin
5590f78c3c8c41d5599541960377ccfce8dc6a94a626adee0f417916bcaf696b
pdf-font-stream PDF embedded font (sfnt) at offset 0x14658 10528 bytes