Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b7a5852e5728768…

MALICIOUS

PDF

123.2 KB Created: 2020-08-29 12:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 165fcb7b2734988d3d17167d5ce0e720 SHA-1: efa4517f9db236dc0104d80ed17a83781492fe98 SHA-256: 8b7a5852e57287688a1f39de20e391be2edacc3bfa2413c272a482be8ecb2a9a
152 Risk Score

Malware Insights

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

The PDF file contains embedded links that point to a known malicious redirector. The document body, though heavily obfuscated, contains text that appears to be a lure related to "HTML 5 lesson notes" and includes the malicious URL. The ML classifier strongly indicates maliciousness, and the PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of a link to known malicious infrastructure.

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.ru/wix?keyword=html+5+ders+notlar%25C4%25B1
    • https://static.usrfiles.com/ugd/b8c837_6b1e24127d5c4175b889c175a960c520.pdf
    • https://static.usrfiles.com/ugd/b8c837_9220537f8c364af78591351a6a777901.pdf
    • https://static.usrfiles.com/ugd/b8c837_1c00696732ad4401bc664535a87739c7.pdf
    • https://static.usrfiles.com/ugd/b8c837_17bd92d207f64c118ff2cb3aafd13f8f.pdf
    • https://static.usrfiles.com/ugd/b8c837_3145514fadbc403c980e1205c7af80c7.pdf
    • https://static.usrfiles.com/ugd/b8c837_ea29acf860ad4b81bda596425837867b.pdf
    • https://static.usrfiles.com/ugd/b8c837_93ba3da61f764956aa760ba5357b868c.pdf
    • https://static.usrfiles.com/ugd/b8c837_1a163df63cb24426ab56e83238a753d9.pdf
    • https://static.usrfiles.com/ugd/b8c837_373e51d2c003456db1c69914a14cc01c.pdf
    • https://static.usrfiles.com/ugd/b8c837_ea6993ee717a4ae3825905e4c241461b.pdf
    • https://static.usrfiles.com/ugd/b8c837_feffc8b05cac426e9b17523a50164663.pdf
    • https://static.usrfiles.com/ugd/b8c837_aed35aa1fc134d989308ae735df3f3d2.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_off00019a86.bin
ebc0c66205eecaa15b97408e97b4ca266c1ef79c221d6a066ab8c4dd73ae161d
pdf-font-stream PDF embedded font (sfnt) at offset 0x19A86 2884 bytes
font_01_sfnt_off0001a4c5.bin
260360b304053bfa34a0aaa7c5d607f6f54e6f25fca83f8f967b18dfa9cbb0c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A4C5 5088 bytes
font_02_sfnt_off0001b5f7.bin
b5edf2b1e6d1f67e8412b0cdae0e718edff27759b9325ca47368990ebcd6452b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B5F7 12768 bytes