Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f042a902f3fa35f…

MALICIOUS

PDF

45.0 KB Created: 2020-03-30 10:45:46 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 557f32f08585b67882fa967fe2f08ad3 SHA-1: 3b927debda2a21a2609f1cde063056c8aaa4f907 SHA-256: 5f042a902f3fa35ffa7f4d3386f13ecd33b1aa83188749b7272bb117887f0cc5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The PDF contains a large number of external links to other PDF files hosted on various domains, indicating a link farm or a distribution mechanism for further content. The ML classifier strongly flagged this PDF as malicious, and the presence of numerous external URIs supports this assessment. The document body itself appears to be obfuscated or corrupted, but the embedded links are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://webdisk.ladse.org/uploads/1/3/0/2/130288399/130288399.html#rubricas+para+evaluar+matematicas+en+sexto+grado+de+primaria
    • http://classicwg.com/uploads/1/3/0/7/130739347/lewonunopixif.pdf
    • http://weproudlybrewsbux.net/uploads/1/3/0/5/130539311/a7ce4a24.pdf
    • http://researchtomorrow.net/uploads/1/3/0/5/130589158/wekerovi-kegazipotedifub-zemujuwu.pdf
    • http://donnace.studio/uploads/1/3/0/2/130289550/72ec557aa06562.pdf
    • http://getfearlessstickers.com/uploads/1/3/0/7/130738785/kifozetiwikuti-pusefuz-goxakejifup.pdf
    • http://hookahdaddy.net/uploads/1/3/0/7/130738741/gumet.pdf
    • http://kurdistantours.net/uploads/1/3/0/5/130590507/pavof.pdf
    • http://fuite-de-piscine.com/uploads/1/3/0/7/130739930/a79ad9444.pdf
    • http://papillonduboisevents.com/uploads/1/3/0/7/130738693/ladewitusu.pdf
    • http://router.gtrnet.com/uploads/1/3/0/8/130813357/9c9b104e6083.pdf
    • http://www.moxace.cl/uploads/1/3/0/7/130739962/3d404a89d544.pdf
    • http://summitagmgmt.com/uploads/1/3/0/7/130739093/6186275.pdf
    • http://soulreporttheplatform.com/uploads/1/3/0/3/130323642/raxeligonuzosepatu.pdf
    • http://lunalashky.com/uploads/1/3/0/2/130273791/d8c17e954.pdf
    • http://mirandaanddevon.com/uploads/1/3/0/8/130874473/9326596.pdf
    • http://rcsac.com/uploads/1/3/0/6/130604579/jojebuvenefu.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_off00007840.bin
ac205cad8e5aa5a01fbf9f9b2b3c2f5fc8615796e312b95a812ae0fabc937946
pdf-font-stream PDF embedded font (sfnt) at offset 0x7840 9904 bytes
font_01_sfnt_off00009ae3.bin
62f01e0afcda60fa4c03556ca1ba6adc0d52a0f6525bbdfe9847e70a1d8d7313
pdf-font-stream PDF embedded font (sfnt) at offset 0x9AE3 1808 bytes