Malicious PDF — malware analysis report

Static analysis result for SHA-256 49826ca994b1fb2b…

MALICIOUS

PDF

45.6 KB Created: 2020-08-05 04:10:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2f70e5c1c187449523a12725974132b1 SHA-1: 3d9cfbdab90d2dfca68bc4a94e13f7e53e468a33 SHA-256: 49826ca994b1fb2b67c9c28a55c75378423237da6bfd5273bfe5ff83434cc57d
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with a critical heuristic firing indicating a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains text related to 'American mathematical society books pdf' and references wkhtmltopdf, suggesting a lure. The primary malicious IOC is the redirector URL, which likely leads to further malicious content. The presence of multiple shopify.com links, some confirmed benign, suggests an attempt to blend in with legitimate content while using a malicious redirector.

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=american+mathematical+society+books+pdf
    • http://files.mxc2020.com/uploads/1/3/0/7/130775921/lemum_xoxel_pesigavolimi_nizavuw.pdf
    • http://files.fullcourtmom.com/uploads/1/3/0/7/130775970/6b7e86733.pdf
    • http://files.shopmorgansmunchies.com/uploads/1/3/1/8/131857445/1756347.pdf
    • https://cdn.shopify.com/s/files/1/0431/0374/8260/files/nalexokajozurononap.pdf
    • https://cdn.shopify.com/s/files/1/0438/2051/5488/files/95455846538.pdf
    • https://cdn.shopify.com/s/files/1/0433/5458/7288/files/delete_commit_history_github.pdf
    • https://cdn.shopify.com/s/files/1/0433/0346/9221/files/zibubadororalizog.pdf
    • https://cdn.shopify.com/s/files/1/0430/6924/3553/files/72153587535.pdf
    • https://cdn.shopify.com/s/files/1/0430/2058/3065/files/78228489564.pdf
    • https://cdn.shopify.com/s/files/1/0433/3345/1944/files/bofaxukaxixifipov.pdf
    • https://cdn.shopify.com/s/files/1/0432/2256/5032/files/govijozanowetukofa.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/50036278562.pdf
    • https://cdn.shopify.com/s/files/1/0434/7750/0057/files/13037709270.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_off0000733c.bin
6dabd1fe71048ae24e6ecbd963d27b1cf490baba4f091a5cb63d1cca7934dff2
pdf-font-stream PDF embedded font (sfnt) at offset 0x733C 5688 bytes
font_01_sfnt_off00008672.bin
cdc832aadc9eb1e8bf8478b3ec676a6e0a8a9a81f10f17983f869a4f14f94c95
pdf-font-stream PDF embedded font (sfnt) at offset 0x8672 10316 bytes