Malicious PDF — malware analysis report

Static analysis result for SHA-256 81cf068a9ab7abd8…

MALICIOUS

PDF

45.9 KB Created: 2020-08-14 20:29:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1542fdf2f61e6b41b27b9264f676ae55 SHA-1: edd15ecf19d3024c49bc7955488a7efb7b09857b SHA-256: 81cf068a9ab7abd80a350e9aceb3c079d4539968b1534326677d1c1a6a1483c5
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to external PDF files. One of these links, 'https://ttraff.com/pify?keyword=reading+skills+list+pdf', is identified as a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body text is heavily obfuscated and appears to contain the malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ttraff.com/pify?keyword=reading+skills+list+pdf
    • http://lumaxek.thenextindianajones.com/uploads/1/3/1/4/131438667/4683092.pdf
    • http://tibis.kelliannmorgan.com/uploads/1/3/2/8/132814930/2539409.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/5107/3174/files/pamunan.pdf
    • https://cdn.shopify.com/s/files/1/0433/8624/1187/files/17544419416.pdf
    • https://cdn.shopify.com/s/files/1/0432/7754/9728/files/95714773812.pdf
    • https://cdn.shopify.com/s/files/1/0437/8922/2045/files/gobupisizara.pdf
    • https://cdn.shopify.com/s/files/1/0437/1985/2200/files/can_t_you_see_chords.pdf
    • https://cdn.shopify.com/s/files/1/0432/1997/6350/files/kimball_data_warehouse_etl_toolkit.pdf
    • https://cdn.shopify.com/s/files/1/0432/5523/4710/files/80479877349.pdf
    • https://cdn.shopify.com/s/files/1/0432/5644/7136/files/negative_impact_of_globalization_in_ethiopia.pdf
    • https://cdn.shopify.com/s/files/1/0431/0253/5840/files/92873562462.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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000604d.bin
3d092c29cc7cd50e9989a4401c3a4475d523d80433ef53d0ec1a68f9d3985dd1
pdf-font-stream PDF embedded font (sfnt) at offset 0x604D 5184 bytes
font_01_sfnt_off00007212.bin
abb0cc590ae0ac6212a0306984959ac3431c1f900093f9c4ea6b643fc36f7356
pdf-font-stream PDF embedded font (sfnt) at offset 0x7212 10288 bytes
font_02_sfnt_off00009546.bin
975089639afea594160f6daa1ae948ffc4125994d61a9fd32dce02580f7b6b15
pdf-font-stream PDF embedded font (sfnt) at offset 0x9546 16312 bytes