Malicious PDF — malware analysis report

Static analysis result for SHA-256 273e50b021f58a4a…

MALICIOUS

PDF

33.0 KB Created: 2020-08-31 10:54:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 11adba754c67bfd1c8fc50744b914012 SHA-1: b23b96d5a3171d968d46d7748a3a559c85887e6a SHA-256: 273e50b021f58a4a24afc0cc74fa2052abfb378dc095e9c242976a7af94667ce
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains a significant number of embedded URLs, with one identified as a known malicious redirector. The document body, though heavily obfuscated, contains references to the malicious URL and other benign-looking URLs hosted on static.usrfiles.com. The presence of a large link farm and a critical heuristic firing for malicious redirectors strongly suggests a phishing or redirection attack. No scripts were extracted, limiting the analysis of specific execution behaviors.

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.ru/wix?keyword=sharron+art+center
    • https://static.usrfiles.com/ugd/4dd980_55ff2a86aaf94d3b879f3bfe7066f692.pdf
    • https://static.usrfiles.com/ugd/b8c837_93879a5317f44462a68c02a82ce7a5da.pdf
    • https://static.usrfiles.com/ugd/2f3ac6_7cc66a505a0a4f85a4a2bbb148d7a5ee.pdf
    • https://static.usrfiles.com/ugd/b8c837_60f6ca8c0a3c476386ae334300d93b9f.pdf
    • https://static.usrfiles.com/ugd/493135_bc29a2a27d31411d8492cf40a9cac4cf.pdf
    • https://static.usrfiles.com/ugd/b8c837_9f72ec573f884ae893bda899ac3d085f.pdf
    • https://static.usrfiles.com/ugd/99965f_12b32b62fec144368b5daf9ccb545d32.pdf
    • https://static.usrfiles.com/ugd/510a18_0d479c87ed434ed6a84744c37150bdab.pdf
    • https://static.usrfiles.com/ugd/fb5067_743da619835e45858f4d4f1096b2cc80.pdf
    • https://cdn.shopify.com/s/files/1/0431/0423/9783/files/95784614118.pdf
    • https://cdn.shopify.com/s/files/1/0433/1061/2635/files/desij.pdf
    • https://cdn.shopify.com/s/files/1/0435/2458/7679/files/safuverojisi.pdf
    • https://cdn.shopify.com/s/files/1/0430/8071/2346/files/77578939421.pdf
    • https://cdn.shopify.com/s/files/1/0430/2677/6227/files/xibovisidokifamit.pdf
    • https://cdn.shopify.com/s/files/1/0437/1228/2789/files/soxonapabubusogano.pdf
    • https://cdn.shopify.com/s/files/1/0431/0823/7473/files/decimal_multiplication_worksheets.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000046a9.bin
c13a10ef36b6ff0c7a46c2587bbffb410dc2aefe90f5907c9ea555ca7a111a5b
pdf-font-stream PDF embedded font (sfnt) at offset 0x46A9 4780 bytes
font_01_sfnt_off000056d5.bin
5cd594b51fb439f139f9fcba817df77e16480ef4284408958681c3ac48556eaa
pdf-font-stream PDF embedded font (sfnt) at offset 0x56D5 9480 bytes