Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d1543ef554a62b8…

MALICIOUS

PDF

47.5 KB Created: 2020-08-27 21:48:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9e90e698e262fd270e4dc68163dbade SHA-1: b8f5db8930d6aa887558a858a44e92a33ab10751 SHA-256: 3d1543ef554a62b89a8e424d8d9e42c9f7b8faa3f0a91f6b9ac7ba17744f8993
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and contains a significant number of embedded links. One critical heuristic identified a link to a known malicious redirector infrastructure, and another identified a link farm composed of numerous external PDF links. The document body, though heavily obfuscated, contains a URL that appears to be part of this link farm. The primary attack pattern involves luring users to click on these links, which likely leads to malicious websites for phishing or malware delivery.

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=old+school+runescape+f2p+smithing+guide
    • http://dosazefa.yumandgetit.com/uploads/1/3/0/7/130739046/gimipatexunusifatom.pdf
    • http://pijin.brijcommunity.org/uploads/1/3/2/3/132303354/mixawav_lunikufazujakoz_nobikok_segipegaxesol.pdf
    • http://kebefe.spanish-expressions.com/uploads/1/3/1/4/131453284/lisevivoxufadadulib.pdf
    • https://cdn.shopify.com/s/files/1/0465/3665/5006/files/12926182900.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/24370467333.pdf
    • https://cdn.shopify.com/s/files/1/0431/0892/5602/files/kijut.pdf
    • https://cdn.shopify.com/s/files/1/0439/8107/8686/files/southern_state_capitals.pdf
    • https://cdn.shopify.com/s/files/1/0428/6893/2767/files/78279469056.pdf
    • https://cdn.shopify.com/s/files/1/0431/2596/4949/files/bone_broth_diet_free.pdf
    • https://cdn.shopify.com/s/files/1/0451/7802/8183/files/95918441211.pdf
    • https://cdn.shopify.com/s/files/1/0438/0891/5613/files/ce2252_strength_of_materials_notes.pdf
    • https://cdn.shopify.com/s/files/1/0431/4100/5480/files/xinonivupafiwa.pdf
    • https://cdn.shopify.com/s/files/1/0429/3292/8671/files/lamosadogoligukuma.pdf
    • https://cdn.shopify.com/s/files/1/0433/9888/9635/files/taux_de_scolarisation_dans_le_monde_2020.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_off000072ee.bin
4c62f9f1071a19beb31ffd9e3b0dcc61e1ce696a35c045bb97282792d68fbbe1
pdf-font-stream PDF embedded font (sfnt) at offset 0x72EE 5728 bytes
font_01_sfnt_off00008641.bin
4fef2c7101e7282c77c5ff4c14ba70926b7fffd033e0e311835128b095544d9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x8641 14040 bytes