Malicious PDF — malware analysis report

Static analysis result for SHA-256 f374c76b37fedfdd…

MALICIOUS

PDF

41.4 KB Created: 2020-08-23 23:51:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-09
MD5: b47335ec9f0129d9d41e7eed26d4d76b SHA-1: 408cb76563e309ef93f95917b22ccf20e8c6a7a9 SHA-256: f374c76b37fedfdd655baeaa50ef58d8dcbd13da652ef653b974ed7de6d79ca0
202 Risk Score

Malware Insights

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

The PDF file contains a deceptive call-to-action disguised as free printable math worksheets. It embeds multiple links, with one specifically pointing to a known malicious redirector. The primary heuristic indicates this is a PDF link farm designed to redirect users to malicious infrastructure, likely for further exploitation or phishing. No scripts were extracted, and the document body is heavily obfuscated, but the presence of the malicious redirector is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=free+printable+math+color+by+number+worksheets In PDF document text
    • http://files.geofuljazz.com/uploads/1/3/1/4/131454850/e1de8352b6063.pdfIn PDF document text
    • http://dosozogaz.goldaes.com/uploads/1/3/1/3/131378950/606088.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/8980/3941/files/zozozanojisedegibuxola.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/6820/9817/files/majesty_worship_his_majesty_chords.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/4682/0245/files/67905113964.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/0428/7383/files/bengali_books_file_free_download.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0465/0552/5398/files/subarachnoid_hemorrhage_guidelines_2019.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/4624/8358/files/42474382403.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/6893/2767/files/tijipogimosod.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/3910/4930/files/3684664614.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8280/9508/files/76212463483.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/7688/5416/files/magazine_article_structure.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/7731/2405/files/logukizavoxezebu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0445/3964/2015/files/forming_storming_norming_performing_deutsch.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/7207/0556/files/lokawobakanagevazawejusu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/0401/0389/files/pigidufopetosevexosi.pdfIn 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://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005f6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F6E 5528 bytes
SHA-256: 3425154a31d16e53b37c1406e8f76031e086654b11843e5ffb47186b5df6487b
font_01_sfnt_off0000720e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x720E 11400 bytes
SHA-256: 813c1f21f50321068f14a892862bc49e3cb32b123bb1bcbac1b939135b228c88