Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c1b335548d6fe5f…

MALICIOUS

PDF

42.5 KB Created: 2020-08-06 08:10:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c658593ed2af5814b2637604455d0cc8 SHA-1: 317f4ffb9fa8e039980c316b9033c4eb4bb6d9db SHA-256: 1c1b335548d6fe5fa04fa06ade4dff39681dcbc611e41ebfc4b965206cf9ee3c
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to external files. One critical heuristic identified a malicious redirector link, and another flagged a link farm structure. The document body, though heavily obfuscated, contains text related to a 'beery vmi manual pdf' and includes the malicious redirector URL, suggesting a lure to a malicious site. The ML classifier also strongly indicated maliciousness.

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=beery+vmi+manual+pdf
    • http://files.vowswithangie.net/uploads/1/3/1/3/131380596/pisukatovimebumepu.pdf
    • http://files.losangeleszetas.org/uploads/1/3/0/9/130969473/tinara_niguwiwijedobot_kuzobaji.pdf
    • http://mekibu.superiorclinics.com/uploads/1/3/1/4/131437919/gifolet.pdf
    • http://files.grapevinehairsalon.com/uploads/1/3/0/9/130969656/gubixetifuboru.pdf
    • https://cdn.shopify.com/s/files/1/0431/5663/5804/files/92527610597.pdf
    • https://cdn.shopify.com/s/files/1/0431/3533/6616/files/kesevelin.pdf
    • https://cdn.shopify.com/s/files/1/0432/0775/3888/files/13453211083.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/29025511016.pdf
    • https://cdn.shopify.com/s/files/1/0433/9620/2661/files/belotero_soft.pdf
    • https://cdn.shopify.com/s/files/1/0428/0382/2755/files/ingersoll_rand_air_compressor_parts_manual.pdf
    • https://cdn.shopify.com/s/files/1/0433/8499/5991/files/architectural_design_patterns.pdf
    • https://cdn.shopify.com/s/files/1/0427/7737/8972/files/povoladagiguparoned.pdf
    • https://cdn.shopify.com/s/files/1/0440/3603/0629/files/15092896568.pdf
    • https://cdn.shopify.com/s/files/1/0428/8492/3555/files/79552317343.pdf
    • https://cdn.shopify.com/s/files/1/0436/1102/9667/files/lista_de_adjetivos_en_ingles_y_espaol.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_off00006925.bin
16b01122f5c00357419cbdd12897e63acf0905ed50969d6637164b4df59b50df
pdf-font-stream PDF embedded font (sfnt) at offset 0x6925 5220 bytes
font_01_sfnt_off00007ae3.bin
2bec4b8a7436474854393cb9f3954adbfb92a2ff43c4f77de58dacfd8a3b1edd
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AE3 10144 bytes