Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f5913a10bd34f25…

MALICIOUS

PDF

41.1 KB Created: 2020-08-10 14:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f3b8fcd3eb75106d0339e2aebeb97dc7 SHA-1: 554a38786a4641a3336e3d8ac6b6b49c5118a349 SHA-256: 1f5913a10bd34f259886d2d533f4c73e3d5c65e5e6efd4caf97b2c1635da259b
152 Risk Score

Malware Insights

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

The PDF contains a link farm and a redirector URL, indicating a malicious intent to direct users to harmful content. The document body, though partially corrupted, contains keywords related to 'calendario escolar' and the malicious URL, suggesting a lure to disguise the malicious redirection. The ML classifier strongly flagged this PDF as malicious.

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/pify?keyword=calendario+escolar+valencia+2020+20+pdf
    • http://files.crappymagic.com/uploads/1/3/1/6/131606677/1315914.pdf
    • http://files.csidelivers.com/uploads/1/3/1/4/131437593/gadazakodi.pdf
    • http://files.cartwheelfoundationintl.org/uploads/1/3/0/9/130969850/1136231.pdf
    • http://files.gtc-elite.org/uploads/1/3/2/6/132682570/netefikuvuboz_fifajog_jubakafa.pdf
    • https://cdn.shopify.com/s/files/1/0431/3110/9540/files/fovam.pdf
    • https://cdn.shopify.com/s/files/1/0431/6617/1293/files/vejigebamabewekisuvol.pdf
    • https://cdn.shopify.com/s/files/1/0432/9252/4700/files/93084192014.pdf
    • https://cdn.shopify.com/s/files/1/0435/1026/8068/files/pagiwebijijixofulut.pdf
    • https://cdn.shopify.com/s/files/1/0431/5676/6882/files/wubamurinowiri.pdf
    • https://cdn.shopify.com/s/files/1/0434/4617/3852/files/31006215817.pdf
    • https://cdn.shopify.com/s/files/1/0429/4184/1575/files/fobafiponapiwu.pdf
    • https://cdn.shopify.com/s/files/1/0431/3799/0813/files/doi_file_sang_word.pdf
    • https://cdn.shopify.com/s/files/1/0428/3708/2271/files/59038731149.pdf
    • https://cdn.shopify.com/s/files/1/0436/7548/4313/files/68888571910.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_off00005ebc.bin
6f7d810e138022837ebfdadd8578f8a3ade7fb01ae1026815ddc9e3e1768b572
pdf-font-stream PDF embedded font (sfnt) at offset 0x5EBC 5388 bytes
font_01_sfnt_off00007126.bin
369d049f1529c8ef1a44f73a99e44e09170a9e3f8dc5d40c797ea3d8ccee0e67
pdf-font-stream PDF embedded font (sfnt) at offset 0x7126 11284 bytes