Malicious PDF — malware analysis report

Static analysis result for SHA-256 71fa27befcaeac66…

MALICIOUS

PDF

37.0 KB Created: 2020-04-07 06:57:17 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 0f168de72bd58682d8a1688e898ec136 SHA-1: d7474f96cac364e3534c9b99c012ded6622c1c60 SHA-256: 71fa27befcaeac6648a84f571a266e051bdcfc67996b2cf4d3af28f7646ed1e3
136 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many of which point to other PDF files hosted on various domains. The heuristic 'PDF_SEO_LINK_FARM' indicates this is a link farm, suggesting a malicious intent to manipulate search engine results or distribute further malware. The ML classifier strongly flagged this PDF as malicious, and the presence of numerous algorithmically generated URLs reinforces this assessment. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://alexiszotos.com/uploads/1/3/0/7/130739098/130739098.html#como+sacar+distancia+focal+de+un+elipse
    • http://luxwatchstore.com/uploads/1/3/1/0/131070983/8688438.pdf
    • http://redengineparty.com/uploads/1/3/1/1/131163638/6507990.pdf
    • http://trinkaus.services/uploads/1/3/1/0/131070327/karuvemonemivud.pdf
    • http://gnshope.com/uploads/1/3/0/5/130550777/401e50d.pdf
    • http://cbcsct.com/uploads/1/3/0/2/130272290/wugop.pdf
    • http://carolineroess.com/uploads/1/3/0/5/130588434/zosoguliridave.pdf
    • http://mindmeetscanvas.com/uploads/1/3/0/4/130436458/falokiwunepodekinuro.pdf
    • http://allanparachinicustomfurniturekauai.com/uploads/1/3/0/2/130272275/pusilo.pdf
    • http://got-a-men.com/uploads/1/3/0/8/130874110/vowudobedun.pdf
    • http://intelligibletechnology.com/uploads/1/3/0/6/130604305/petakiwowuxitatus.pdf
    • http://robinsoncoffeeroastingcompany.com/uploads/1/3/1/1/131164506/giwubegomesegitobop.pdf
    • http://lanigiromusic.com/uploads/1/3/1/4/131405951/xameserudosez.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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000646c.bin
19e6c363095e4104b63e854068b54aea88df7a0ebc1c838b4031d99a5b955e16
pdf-font-stream PDF embedded font (sfnt) at offset 0x646C 8920 bytes