Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d1a4da96243dca3…

MALICIOUS

PDF

39.3 KB Created: 2020-08-30 11:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e8e5e3d27dd2049ff5b837af64c6ba5b SHA-1: fdf68b54ce55bacdbe5809e8610bc3687af61293 SHA-256: 8d1a4da96243dca317d6635215ba9e2d55b9627a98198d319d7466e39df4cb1a
154 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, many pointing to external resources, which is indicative of a link farm. One of these links, 'https://ttraff.me/wix?keyword=teaching+vocabulary+8th+grade', is flagged as a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'teaching vocabulary 8th grade', likely a lure to disguise the malicious intent. The ML classifier also strongly flagged this PDF as malicious.

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.me/wix?keyword=teaching+vocabulary+8th+grade
    • https://static.usrfiles.com/ugd/b8c837_c23f1188a5154b8980cb8176da2cb52b.pdf
    • https://static.usrfiles.com/ugd/b8c837_29c6e5411e934a018cb052603a8311d5.pdf
    • https://static.usrfiles.com/ugd/934fc3_2e87f0d1643e4cfcbce28ddbe2849540.pdf
    • https://static.usrfiles.com/ugd/5d2cf3_ea06f914531e48209ee3bb4631b63265.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jikoleluvotejagumali.pdf
    • https://static.usrfiles.com/ugd/510a18_1d5d35b1a8ac4c268f9dec38ee209507.pdf
    • https://static.usrfiles.com/ugd/10b11f_d01ea955a75a4de48a1baca89790376d.pdf
    • https://static.usrfiles.com/ugd/374ce0_d06f250f844e4b4cb21ec9f395de9a2d.pdf
    • https://static.usrfiles.com/ugd/87a178_9279059bc1004b5faa4dbbcf0b2f34b5.pdf
    • https://static.usrfiles.com/ugd/b8c837_6089b2989afa43249875c1a84d36af5a.pdf
    • https://cdn.shopify.com/s/files/1/0428/7476/5475/files/madotozuli.pdf
    • https://cdn.shopify.com/s/files/1/0431/9232/0161/files/administrao_estratgica_fernandes_e_berton.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_off00005ba6.bin
a5106c473a7b4bd71c11d057a81062119f0f69ea2a5b0fd4d8890eee1e502301
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BA6 5468 bytes
font_01_sfnt_off00006e36.bin
07ab2cd544e4fdc0e7e809e7d4dcd25bd1e329693502a9c4aa971a5f770514c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E36 10152 bytes