Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff54e491c9e195c…

MALICIOUS

PDF

48.9 KB Created: 2020-03-25 01:39:14 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 29d3b8d473e0bbcb7e127025cb713704 SHA-1: b1ba298827b8bdddd1882a479916c8ca19c8dc29 SHA-256: bff54e491c9e195ce60fe65c108d09e427f1267f64c77c226c7fa1c6912adf09
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The PDF contains a large number of external links, many of which point to similarly structured URLs on different domains, indicating a link farm or SEO abuse tactic. The document body, though partially corrupted, suggests an educational theme ('Exercice sur le pass é compos é cm2 à imprimer') which is likely a lure to disguise the malicious intent. The ML classifier strongly flagged this PDF as malicious, and the PDF_SEO_LINK_FARM heuristic confirms the suspicious linking behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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://toadblue.net/uploads/1/3/0/5/130538994/130538994.html#exercice+sur+le+pass%C3%A9+compos%C3%A9+cm2+%C3%A0+imprimer
    • http://myjamesandrews.com/uploads/1/3/0/7/130739878/sonanejo-doramiv.pdf
    • http://www.solidresearch.info/uploads/1/3/0/2/130270811/fawidedumagero-nozibanamoketap.pdf
    • http://bronxrollingdoor.com/uploads/1/3/0/2/130272582/vefexopelefinu.pdf
    • http://rws1301.com/uploads/1/3/0/8/130873791/putevulujan.pdf
    • http://mx.mauirunning.com/uploads/1/3/0/7/130739577/votunidikotomep.pdf
    • http://enquiry.s31.in/uploads/1/3/0/5/130588754/cd35c.pdf
    • http://detourister.com/uploads/1/3/0/5/130544584/6713531.pdf
    • http://joesk9care.com/uploads/1/3/0/2/130270804/3477291.pdf
    • http://autodiscover.farobankcreative.com/uploads/1/3/0/5/130588779/nanor.pdf
    • http://www.thegrizzlybeardco.com/uploads/1/3/0/7/130774970/6435487.pdf
    • http://jimbits.net/uploads/1/3/0/3/130323266/mivitebal.pdf
    • http://saturdaybinge.com/uploads/1/3/0/6/130620849/pixudisajowupinarafi.pdf
    • http://gcipturkiye.org/uploads/1/3/0/6/130603819/8771635.pdf
    • http://helowatchinc.com/uploads/1/3/0/8/130874523/voredetezoparilixo.pdf
    • http://thegoldguarantee.com/uploads/1/3/0/8/130813403/5456228.pdf
    • http://www.freeformwithjules.com/uploads/1/3/0/6/130639569/jamanuditigebuvuwu.pdf
    • http://not-trump-2020.org/uploads/1/3/0/8/130814042/vuramezusademo.pdf
    • http://noroplan.com/uploads/1/3/0/6/130621873/74be643a4214a.pdf
    • http://martinezcommercialcleaning.com/uploads/1/3/0/4/130436207/fevebasapumilax-fobosapekaxifud.pdf
    • http://caseysmithdesign.com/uploads/1/3/0/4/130483527/8382778.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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007323.bin
79c24083658959bcea49987bebba7d2087da56bb229dd4286fbcee2424f67f5d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7323 9212 bytes
font_01_sfnt_off00009436.bin
915baeb1e29b1296448dc25187851e9706b77add1d29a836586dd6d4826066cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x9436 2600 bytes
font_02_sfnt_off00009d5f.bin
74cde96fec7a8e55a6e3b3b02ead569c1f81e2235d29f561a12d4ae7dee7f6be
pdf-font-stream PDF embedded font (sfnt) at offset 0x9D5F 16144 bytes