Malicious PDF — malware analysis report

Static analysis result for SHA-256 81fc385735af00a4…

MALICIOUS

PDF

41.6 KB Created: 2020-08-21 16:57:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0c871e5a13eceba0dc1683c538460ffd SHA-1: fdf400733ca076a7b83365af9552bf98500adbf5 SHA-256: 81fc385735af00a45cf22e658c725524b6dec6da8f51922a474124dc2b89fb71
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with a critical heuristic identifying a link to a known malicious redirector at 'https://ttraff.cc/pify?keyword=alcoholic+fatty+liver+treatment+guidelines'. Another critical heuristic indicates the PDF acts as a link farm, with many external links, predominantly hosted on cdn.shopify.com. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the presence of the malicious redirector suggests a phishing or malware delivery attempt.

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.cc/pify?keyword=alcoholic+fatty+liver+treatment+guidelines
    • http://files.minisodaaussies.com/uploads/1/3/0/9/130969893/7999909.pdf
    • http://files.a1moments.com.au/uploads/1/3/1/4/131407148/f1cb1e3ca65cf3.pdf
    • http://files.thewritesourcetwcspublishing.com/uploads/1/3/1/8/131856121/vumegofu.pdf
    • https://cdn.shopify.com/s/files/1/0429/9869/4049/files/author_s_style.pdf
    • https://cdn.shopify.com/s/files/1/0465/9327/8117/files/avadh_university_phd_form_2018.pdf
    • https://cdn.shopify.com/s/files/1/0431/3219/0876/files/96507090312.pdf
    • https://cdn.shopify.com/s/files/1/0429/9869/4049/files/31055871760.pdf
    • https://cdn.shopify.com/s/files/1/0431/0496/0661/files/niwejelogawaketakare.pdf
    • https://cdn.shopify.com/s/files/1/0435/8907/5102/files/ritogerisagusuk.pdf
    • https://cdn.shopify.com/s/files/1/0431/3304/2839/files/muxekopapifedij.pdf
    • https://cdn.shopify.com/s/files/1/0434/0255/9655/files/anemia_megaloblastica_perniciosa.pdf
    • https://cdn.shopify.com/s/files/1/0432/7519/0422/files/motezowujena.pdf
    • https://cdn.shopify.com/s/files/1/0450/1661/3014/files/bobcat_610_service_manual_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/4447/0945/files/bsc_physics_syllabus_sambalpur_university.pdf
    • https://cdn.shopify.com/s/files/1/0431/1423/4017/files/verutisulazas.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_off0000641f.bin
5160b3f3b046bde40c7629d4fbe908d15d7ff64bcafbe734801051a44543186b
pdf-font-stream PDF embedded font (sfnt) at offset 0x641F 5588 bytes
font_01_sfnt_off00007700.bin
4d3f20bd1b9abaed46088be65853a04ca48abd4e619ce453f2ffdf19acacfa96
pdf-font-stream PDF embedded font (sfnt) at offset 0x7700 10048 bytes