Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8c72b55ba650a1c…

MALICIOUS

PDF

40.2 KB Created: 2020-08-31 06:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cbb450ffe33374fe9c47f390e998e2ce SHA-1: b67a72aaa85f95698b4c7ef5ab545a2249562ae3 SHA-256: d8c72b55ba650a1cbbec7825d08341de481b3c5f00f0be8b12c23b0074adcf89
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to static.usrfiles.com, but one critical link directs to a known malicious redirector at ttraff.cc. The document body, though heavily obfuscated, contains text related to 'printable blank comic strips template' and the malicious URL, suggesting a lure to a malicious site disguised as a template resource. The ML classifier 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.cc/wix?keyword=printable+blank+comic+strips+template
    • https://static.usrfiles.com/ugd/0d2908_de2f0f78d55b46e094f558866c3e1a3c.pdf
    • https://static.usrfiles.com/ugd/b8c837_adcbfd0dd84c46919f0b95b7516ae856.pdf
    • https://static.usrfiles.com/ugd/078c79_0798cd22ced747c494d9308ac81ed4b0.pdf
    • https://static.usrfiles.com/ugd/93c935_0d0c3fb1341844d4beffb16e3ef04477.pdf
    • https://static.usrfiles.com/ugd/db93e9_22c7c66bd24a485a8f1b813db880fe24.pdf
    • https://cdn.shopify.com/s/files/1/0431/7023/4524/files/xirapa.pdf
    • https://cdn.shopify.com/s/files/1/0431/9959/4656/files/tilirovositobunib.pdf
    • https://static.usrfiles.com/ugd/d99ef3_9d43ca0935084e7c8a15bcddb1327b39.pdf
    • https://static.usrfiles.com/ugd/7ff653_7001863e0f83495d9eb60d3bcb3155b4.pdf
    • https://static.usrfiles.com/ugd/5d2cf3_c3fffbd3b2a54a86af73098289d44f26.pdf
    • https://static.usrfiles.com/ugd/b8c837_2986a01e740a42bebdd0852c6651dd67.pdf
    • https://static.usrfiles.com/ugd/430cb2_6c05556992b24180a1b89d6828d037fd.pdf
    • https://static.usrfiles.com/ugd/97634b_da37451de9ac49808f7b33689e70b184.pdf
    • https://static.usrfiles.com/ugd/ac51ce_cb04a737b1414b90b9dc8cbd9bb7f3cd.pdf
    • https://static.usrfiles.com/ugd/5ed537_1e9be139aaf04ae6ba7e2e5b410ae666.pdf
    • https://static.usrfiles.com/ugd/b8c837_2a7a3304c6474d6ca47f26549268ee81.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_off00005f2e.bin
34ef33ba785c4b8ccce4a222c645a18adaedb1041a38d8287561e4854e2b4f4f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F2E 5284 bytes
font_01_sfnt_off00007101.bin
609e31fca9e07e8ac9776979489c1be230a1df87be64d4a78131cdc63ac35506
pdf-font-stream PDF embedded font (sfnt) at offset 0x7101 10172 bytes