Malicious PDF — malware analysis report

Static analysis result for SHA-256 18c7b313b055b7cf…

MALICIOUS

PDF

36.5 KB Created: 2021-10-24 12:21:19 +02:00 Authoring application: Writer (via OpenOffice 4.1.10) First seen: 2021-11-02
MD5: 85a81ecc14bba73ab8e335c6940617b9 SHA-1: 62e11f2a482b418de3172a3dd273bb66ed136f14 SHA-256: 18c7b313b055b7cffe7d3374e37f5705364fa5499a5419ee5c6c21a568d52cd2
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a heuristic firing for PDF_URL_SHORTENER_URI, indicating the presence of a shortened URL. This URL, https://jertoniko.page.link/c1DV, is likely used to redirect users to a malicious site. The ML classifier also flagged the PDF as malicious. While no scripts were explicitly extracted, the combination of a shortened URL and evasion techniques suggests an attempt to deliver a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7570

Heuristics 4

  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • Clickable URI uses URL shortener medium PDF_URL_SHORTENER_URI
    PDF contains a clickable HTTP(S) action whose destination is a URL shortener. This hides the final landing page from static review and is common in phishing redirect PDFs.
  • 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://jertoniko.page.link/c1DV In PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off00000849.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x849 48680 bytes
SHA-256: 8c34682fc5e6e6a391c18cd7cc3bd98dd204348ead104ff3ab6ceab4df5a3cf6

Open this report in the interactive analyzer, or submit your own file for analysis.