Malicious PDF — malware analysis report

Static analysis result for SHA-256 13c43d4c722c8ca0…

MALICIOUS

PDF

39.5 KB Created: 2020-06-28 09:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3930f15af9e7e55b72166a97e0fcdeaa SHA-1: 4ae67367f65edf53a94fa897ed21b44644a21e09 SHA-256: 13c43d4c722c8ca0f5007da2b031bb901fef8fcf1f0fc2d15a676a63da1bb57d
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are dynamically generated and point to PDF files, indicating a link farm or SEO spam tactic. The ML classifier strongly flagged this PDF as malicious. The embedded URLs suggest a phishing or spam campaign designed to redirect users to potentially harmful content.

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://files.stampgeneral.com/uploads/1/3/1/3/131380107/131380107.html#paragraph+on+physical+exercise
    • http://rinjaniakria.com/uploads/1/3/0/4/130483200/44ade47b9.pdf
    • http://derrickkeeton.com/uploads/1/3/1/4/131406867/6d446f9.pdf
    • http://indosurftravelco.com/uploads/1/3/1/8/131871863/3719594.pdf
    • http://coreducate.net/uploads/1/3/1/4/131454306/pabafobotavubebemog.pdf
    • http://admin.america.rentals/uploads/1/3/0/8/130874364/babidunuxox_lunebuvole_gatowenibuxa.pdf
    • http://midwestundergroundinc.com/uploads/1/3/0/2/130289291/padaf.pdf
    • http://folkvangr.online/uploads/1/3/1/4/131407370/veliridet_gevofugakome_fedisemot_pesetotakediv.pdf
    • http://myphipi.com/uploads/1/3/1/0/131070398/eb39379a61aaecb.pdf
    • http://files.dreamscapemetal.com/uploads/1/3/0/6/130620968/sanolor.pdf
    • http://virkelighedenkalder.dk/uploads/1/3/0/9/130969972/jokojapo-kotamipeduja-kenab-sipib.pdf
    • http://mail.townofhelvetia.com/uploads/1/3/0/8/130873923/najusut.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://jubowut.files.wordpress.com/2020/06/55662454365.pdf
    • https://riwimatuko.files.wordpress.com/2020/06/gokofodewusije.pdf
    • https://sexedituf.files.wordpress.com/2020/06/vakevifuwarurogufefimuv.pdf
    • https://xukudegexe.files.wordpress.com/2020/06/27381090034.pdf
    • https://rokipes.files.wordpress.com/2020/06/popaninarosovubo.pdf
    • https://fapezajudu.files.wordpress.com/2020/06/sajemawigidobatagiketu.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_off00005cee.bin
e2cac3bd2a7d46b80bd4011e50f4b09d52029de0af56b1072c79275d6901cdb8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CEE 5072 bytes
font_01_sfnt_off00006e23.bin
c7e5b6ab6affc28e00b14923b6691f17a27f86ee81dd35d9496828ef5d2ac610
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E23 10280 bytes