Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fceada606de32c1…

MALICIOUS

PDF

43.6 KB Created: 2020-08-31 16:47:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 101fe6605c54799cd34cbea5920c7ba7 SHA-1: 5bb58cee82c0e35741de1bbf44edf21ef30c5657 SHA-256: 1fceada606de32c16349164942089e79e086aa6b536e97b3213c9f15bc3ae928
152 Risk Score

Malware Insights

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

The PDF contains a link farm and a critical heuristic firing for a malicious redirector. The document body, though heavily obfuscated, contains text suggesting it is a lure for 'destination b1 answer keys pdf'. The primary malicious IOC is the redirector URL, which is likely used to host further malicious content or phishing pages. The ML classifier also strongly indicated maliciousness.

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=destination+b1+answer+keys+pdf
    • https://static.usrfiles.com/ugd/5e8de6_44bdeb933e364a4dba17bd0f78df7701.pdf
    • https://static.usrfiles.com/ugd/3bcfef_9e223ea354c7461f96543d577f0cdc57.pdf
    • https://static.usrfiles.com/ugd/ca300b_b596b6a8af63420bb704ad470e191569.pdf
    • https://static.usrfiles.com/ugd/6908d7_76720296237045958edfdfd1156b359b.pdf
    • https://static.usrfiles.com/ugd/0d002d_322a23958f2c45f78a6a2064bd544453.pdf
    • https://static.usrfiles.com/ugd/c068f8_e8cfb589f4e94ec8b7ec8e627825554c.pdf
    • https://cdn.shopify.com/s/files/1/0431/0954/8188/files/99028916420.pdf
    • https://cdn.shopify.com/s/files/1/0430/3116/7137/files/7867839905.pdf
    • https://cdn.shopify.com/s/files/1/0434/3883/3816/files/zamujewofazulafarevafow.pdf
    • https://cdn.shopify.com/s/files/1/0463/5803/6646/files/digital_tv_manual_tuning_frequency_malaysia.pdf
    • https://cdn.shopify.com/s/files/1/0430/4578/1665/files/pobizejinatuxubafaduro.pdf
    • https://static.usrfiles.com/ugd/238140_f54b03935519496ba8c75de35ef7a941.pdf
    • https://static.usrfiles.com/ugd/b8c837_7eb12e43ac1a4dfba1729cfb09986dba.pdf
    • https://static.usrfiles.com/ugd/10a4aa_fff7f95f883c4aafa245da90f72c1aae.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005ebc.bin
0e38d2fba5366a87297b6583a8a8f972efb900ba9cf0b62cc9f00a73444e7dd1
pdf-font-stream PDF embedded font (sfnt) at offset 0x5EBC 5240 bytes
font_01_sfnt_off000070af.bin
9f3fb154929f020cd8680abd646d97f607a78001a665e837fc24b4763159ff90
pdf-font-stream PDF embedded font (sfnt) at offset 0x70AF 10196 bytes
font_02_sfnt_off00009392.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x9392 4324 bytes