Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c26bae52b94b649…

MALICIOUS

PDF

34.5 KB Created: 2020-07-31 16:58:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e839904687c8c3391a79278fb8d952f1 SHA-1: 6fec828146aa8ed756b4eac10ce2147d52d09970 SHA-256: 7c26bae52b94b6493b720e7ca4a46ec7d65fcadf48b5b051f5a0498f6c9f8512
154 Risk Score

Malware Insights

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

The PDF contains numerous links, including one to a known malicious redirector, disguised as a solution manual. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK indicates that the primary link leads to malicious infrastructure. The ML classifier also strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains the target URL and other PDF links, suggesting a lure to download further malicious content.

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/pify?keyword=actuarial+mathematics+bowers+solution+manual+pdf
    • http://files.thecornerstohr.com/uploads/1/3/0/7/130775023/f8e54af591b7ad6.pdf
    • http://files.sierrastonefabrication.com/uploads/1/3/1/4/131482864/nazunegetu.pdf
    • http://files.daytoncommunitynews.com/uploads/1/3/0/9/130969573/d594ebc04509349.pdf
    • https://cdn.shopify.com/s/files/1/0435/1046/4667/files/10963956029.pdf
    • https://cdn.shopify.com/s/files/1/0433/6926/7354/files/daraf.pdf
    • https://cdn.shopify.com/s/files/1/0437/3312/3221/files/44061767469.pdf
    • https://cdn.shopify.com/s/files/1/0432/7079/9510/files/lopisixidominiwapozex.pdf
    • https://cdn.shopify.com/s/files/1/0431/5657/0266/files/xiwen.pdf
    • https://cdn.shopify.com/s/files/1/0430/0580/4698/files/jodofidozoboxirosebipe.pdf
    • https://cdn.shopify.com/s/files/1/0430/1609/3849/files/54254667435.pdf
    • https://cdn.shopify.com/s/files/1/0428/2338/5247/files/46049154387.pdf
    • https://cdn.shopify.com/s/files/1/0438/6213/0848/files/75858566377.pdf
    • https://cdn.shopify.com/s/files/1/0431/5981/4306/files/nateta.pdf
    • https://cdn.shopify.com/s/files/1/0432/0601/7186/files/17474120782.pdf
    • https://cdn.shopify.com/s/files/1/0431/7321/6412/files/vivekam.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_off00004814.bin
a07e2cb523e1de3ea6bc2320d723944a3eedba3e4c1d7bbcbb23c2a3c24300dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x4814 5616 bytes
font_01_sfnt_off00005b11.bin
c691979cc677f9d34fd99ce47d0759f0c97f0aa227f3a3d7cebc2cd3ed71e982
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B11 9820 bytes