Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdd8234e1085c632…

MALICIOUS

PDF

45.8 KB Created: 2020-08-21 09:20:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: df12daf1c668edecc8bd0f05c2fc4d6e SHA-1: cdf8281ce486532261c48559cbcf8e6644510930 SHA-256: fdd8234e1085c6326f0e3e083257d74af8eebc934f4dfde1a5e7ee9b4377c7d9
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a lure for a 'grammar worksheet grade 6' and embeds a large number of external links, many pointing to PDF documents. One of these links, https://ttraff.com/pify?keyword=grammar+worksheet+grade+6, is identified as a malicious redirector. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the extensive link farm and the malicious redirector indicate a phishing or redirection attack.

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.com/pify?keyword=grammar+worksheet+grade+6
    • http://files.ieselpicarral.com/uploads/1/3/1/4/131454102/roteba.pdf
    • http://xoduvuda.kitsuneillustrations.com/uploads/1/3/1/6/131637649/7784417.pdf
    • http://ninitij.doorcountybeachrentals.com/uploads/1/3/1/0/131070493/loxabufudino-giveb-tumukofajixo.pdf
    • http://files.wortcunner.com/uploads/1/3/1/8/131856290/zomivelerese.pdf
    • https://cdn.shopify.com/s/files/1/0431/7960/6177/files/15358301094.pdf
    • https://cdn.shopify.com/s/files/1/0434/6196/8025/files/c_language_programming.pdf
    • https://cdn.shopify.com/s/files/1/0431/0846/6845/files/34538120995.pdf
    • https://cdn.shopify.com/s/files/1/0431/1285/7754/files/world_encyclopedia_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0432/7145/4883/files/authoritarianism_definition.pdf
    • https://cdn.shopify.com/s/files/1/0431/6053/5196/files/xenalexovuxunuvedeb.pdf
    • https://cdn.shopify.com/s/files/1/0432/6568/7717/files/36507386799.pdf
    • https://cdn.shopify.com/s/files/1/0436/5503/7093/files/jj_benitez_caballo_de_troya_4.pdf
    • https://cdn.shopify.com/s/files/1/0433/9829/9813/files/seganijusosidevepujares.pdf
    • https://cdn.shopify.com/s/files/1/0440/3301/5958/files/segmentation_targeting_and_positioning_notes.pdf
    • https://cdn.shopify.com/s/files/1/0429/0599/3375/files/wokawazexenajajifo.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_off0000742c.bin
242dc1755bcdef8ee21df480fbe1a85ff642071490041e87abf6352dd46a5569
pdf-font-stream PDF embedded font (sfnt) at offset 0x742C 5548 bytes
font_01_sfnt_off00008706.bin
75e17bbb196839fa24cc624ad664dcc9af0b6873c1d1f471a33de55e539a804f
pdf-font-stream PDF embedded font (sfnt) at offset 0x8706 10512 bytes