Malicious PDF — malware analysis report

Static analysis result for SHA-256 232c4e336abd9254…

MALICIOUS

PDF

44.0 KB Created: 2020-07-07 11:06:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1f652859c9082ef0416c66623e168476 SHA-1: cd7cf877057cbd36b35acda39463c82e73c4e624 SHA-256: 232c4e336abd9254af26f6aab82fc9bf908c98bde753ef184c0dd2fae594aee9
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, with one specifically pointing to a known malicious redirector. The ML classifier strongly indicated maliciousness. The document body appears to be obfuscated text related to 'stoichiometry lecture notes pdf', likely a lure to disguise the malicious links.

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/wb?keyword=stoichiometry%20lecture%20notes%20pdf#stoichiometry+lecture+notes+pdf
    • http://files.stmarymagdalenewpg.org/uploads/1/3/1/8/131856531/badifa.pdf
    • http://files.larryssportsexchange.com/uploads/1/3/0/8/130874128/folerezome.pdf
    • http://files.grundmeyerleadersearch.com/uploads/1/3/1/6/131636990/sifixoj_jutixepipi_bevasagipaxuja_sivosukisozi.pdf
    • http://files.hallielee.com/uploads/1/3/2/8/132815961/5788720.pdf
    • http://files.mpowertheworld.net/uploads/1/3/2/7/132740415/kadisetiwebuget_rofajanagojata.pdf
    • http://files.mackeiganmarketing.com/uploads/1/3/1/4/131452732/sodopafesub.pdf
    • http://files.globalisationandcities.com/uploads/1/3/1/6/131607174/jilaxafufusekiw.pdf
    • http://files.valleyrootsfoodhub.com/uploads/1/3/0/7/130740344/fa8b50ce.pdf
    • http://files.linhr.com/uploads/1/3/1/0/131070189/tabotusatoboza.pdf
    • https://kogezes.files.wordpress.com/2020/06/62340349030.pdf
    • https://wiziroj.files.wordpress.com/2020/07/99814786019.pdf
    • https://xifoburufo.files.wordpress.com/2020/07/9563621868.pdf
    • https://vavivimabefu.files.wordpress.com/2020/07/58751120410.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_off00006d88.bin
fd72ea43e6b481cdc26853f04fc166d1002df76031d2a1671507a6d94f269bf6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D88 5272 bytes
font_01_sfnt_off00007f47.bin
1f95445ed4ade555465ba5010f1e55aeb80e1d5537610a6f4f8f6c05ad1efbed
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F47 10772 bytes