Malicious PDF — malware analysis report

Static analysis result for SHA-256 40c091ae8107e7ab…

MALICIOUS

PDF

42.9 KB Created: 2020-09-01 04:03:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2b8656f7fab95bb583cdf73122f5c499 SHA-1: c78c9d35288449ed70b20b68f66eae10a846d8ff SHA-256: 40c091ae8107e7ab1629db1bcc7010697d1b87b1024de9157cc40f6e17ffa88d
154 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that appears to be part of a link farm, with numerous other PDFs hosted on static.usrfiles.com. This suggests a phishing or malware distribution attempt.

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/wix?keyword=castor+informatique+2018+entrainement
    • https://static.usrfiles.com/ugd/2f3ac6_42b04b49bdf9464fad63c811393cade0.pdf
    • https://static.usrfiles.com/ugd/8cbfce_93dc69fd734a44bc880a74c7aa49e866.pdf
    • https://static.usrfiles.com/ugd/6c032c_f3a9960db30d4a8d800587e4758de4fd.pdf
    • https://static.usrfiles.com/ugd/db1da1_a823faf3b1314a7d890566e25d36047d.pdf
    • https://static.usrfiles.com/ugd/b4609a_8f9c4b25030e49b286fc63343275f69d.pdf
    • https://static.usrfiles.com/ugd/0c268c_ef9def4301eb4a748b1ddfb2c1d63672.pdf
    • https://static.usrfiles.com/ugd/c6ac46_82a9b259145f44998633de4f3c6b415e.pdf
    • https://static.usrfiles.com/ugd/b8c837_9efea030c12f4ddcbf79c469a37b49f8.pdf
    • https://static.usrfiles.com/ugd/5fd5c1_b92567ed195a451289c79bf5cd88c6ac.pdf
    • https://static.usrfiles.com/ugd/ecec20_8b7b930ea1a6447487e18d759fbc0654.pdf
    • https://static.usrfiles.com/ugd/07e02c_bd00b384c8404795bb0f94c6c83a8e9d.pdf
    • https://cdn.shopify.com/s/files/1/0429/2889/8211/files/30106010270.pdf
    • https://cdn.shopify.com/s/files/1/0430/5662/7866/files/77439605838.pdf
    • https://cdn.shopify.com/s/files/1/0437/1097/2056/files/fifedubamulikubenujo.pdf
    • https://cdn.shopify.com/s/files/1/0447/9765/7248/files/remove_inactive_facebook_friends.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_off0000660c.bin
17c13ef9d3ec69377d84d6353ec626f2ae7b37d82443eb05327e02bfcc85f053
pdf-font-stream PDF embedded font (sfnt) at offset 0x660C 5432 bytes
font_01_sfnt_off0000786d.bin
b79a1373d34cde2a8f022e019f43fff8448d8fa76fce174b3d5157be0fa1137c
pdf-font-stream PDF embedded font (sfnt) at offset 0x786D 11572 bytes