Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ca94aa7478dca6b…

MALICIOUS

PDF

34.6 KB Created: 2020-08-31 05:39:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 092feeff541a07c5b75092c331a86384 SHA-1: 74ba288f1a0b61554ff6d86b33f77562a1e17d61 SHA-256: 8ca94aa7478dca6b72b04bd630152d1128f0d6142ea8ec050af3868036f794dd
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 Malicious Link T1059.001 PowerShell

The PDF contains a significant number of embedded links, many of which point to a link farm hosted on `static.usrfiles.com`. One of the primary links, `https://ttraff.cc/wix?keyword=Dr.+uke+berisha+kline`, is identified as a malicious redirector. This suggests the document's purpose is to lure users into clicking these links, which likely lead to malicious websites for phishing or malware delivery. The ML classifier strongly supports the malicious nature of this PDF.

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.cc/wix?keyword=Dr.+uke+berisha+kline
    • https://static.usrfiles.com/ugd/76de1a_875738b769bf47f1b97e08ab702a6df5.pdf
    • https://static.usrfiles.com/ugd/b8c837_30a319ecbfb8443d8351d97a3c243ee1.pdf
    • https://static.usrfiles.com/ugd/b8c837_cdb8c915d5d04509a775216ffb8b7c2c.pdf
    • https://static.usrfiles.com/ugd/cc14e4_4f4267e9cc474304aedfae925cd44d94.pdf
    • https://static.usrfiles.com/ugd/eb4c03_c151bbb255e54e8dbecd0f216ec6651b.pdf
    • https://static.usrfiles.com/ugd/e2b09b_d56ecce092c14947abf722cd1ac0288c.pdf
    • https://static.usrfiles.com/ugd/0047a4_9afa850c07944a59becf9bcf623dc62f.pdf
    • https://static.usrfiles.com/ugd/b8c837_d875d13cd1e6451d9ac5728e0dbfcc71.pdf
    • https://static.usrfiles.com/ugd/b8c837_e023013883454fd4b69c07d462d57702.pdf
    • https://cdn.shopify.com/s/files/1/0430/9073/9361/files/pusarim.pdf
    • https://cdn.shopify.com/s/files/1/0438/3732/5472/files/emoji_keyboard_android.pdf
    • https://cdn.shopify.com/s/files/1/0431/6486/0580/files/80595339595.pdf
    • https://static.usrfiles.com/ugd/4dd980_87943158d894470bb2a762536962fe2b.pdf
    • https://static.usrfiles.com/ugd/49be48_ae25c081961245e5a5b2fe86c952a181.pdf
    • https://static.usrfiles.com/ugd/b8c837_f1b405fb8ba84b7eadd8756f7b612aad.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_off00004a23.bin
d8da1b4fec79ef39e2e7822275b7f02b7cbbd4cd05af39a8dc2dacb34ac7aba6
pdf-font-stream PDF embedded font (sfnt) at offset 0x4A23 5008 bytes
font_01_sfnt_off00005b29.bin
b10bf11cd742b7c863452eb3d553e1bf38c146200bf137848a4090411a83c263
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B29 10204 bytes