Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7aa2afa649e0666…

MALICIOUS

PDF

58.5 KB Created: 2020-08-09 20:13:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1fbcdc10d9a37051b0ed856f10689bc4 SHA-1: 63c27e167a74351ab76cf379ddbfc924e8d7fc41 SHA-256: b7aa2afa649e0666c9fa868ff2a262fc53e49b65eacadce16b9a1a472f027aae
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, including a known malicious redirector at 'https://ttraff.cc/pify?keyword=ecg+valores+normales+pdf'. The ML classifier strongly flagged this PDF as malicious, and heuristic rules indicate it is a link farm designed to redirect users. The document body, though heavily obfuscated, also contains the redirector URL and several other Shopify-hosted PDF links.

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=ecg+valores+normales+pdf
    • http://files.marleemoo.com/uploads/1/3/1/4/131437532/lexukumif.pdf
    • http://files.hermonpresbyterian.org/uploads/1/3/2/6/132681219/mavuviga_mutulazutezu_wugujeka_dejivofif.pdf
    • http://files.drrobyngraber.com/uploads/1/3/1/3/131384281/dabapusori.pdf
    • https://cdn.shopify.com/s/files/1/0429/5340/8675/files/punjabi_ring_tone.pdf
    • https://cdn.shopify.com/s/files/1/0437/1628/0475/files/42780095864.pdf
    • https://cdn.shopify.com/s/files/1/0433/8089/9991/files/29125304844.pdf
    • https://cdn.shopify.com/s/files/1/0437/7670/4669/files/asian_paints_colour_book_2020.pdf
    • https://cdn.shopify.com/s/files/1/0429/3846/6467/files/wegaxedojarijitiwopufizu.pdf
    • https://cdn.shopify.com/s/files/1/0430/9729/2949/files/31366152178.pdf
    • https://cdn.shopify.com/s/files/1/0428/5713/6294/files/dapumizupuwofemazina.pdf
    • https://cdn.shopify.com/s/files/1/0429/9502/4025/files/43780046575.pdf
    • https://cdn.shopify.com/s/files/1/0431/0496/0676/files/61083506033.pdf
    • https://cdn.shopify.com/s/files/1/0434/5282/5750/files/37546996578.pdf
    • https://cdn.shopify.com/s/files/1/0438/2749/5072/files/baladiraxijomeritefi.pdf
    • https://cdn.shopify.com/s/files/1/0431/2177/0656/files/jirofijite.pdf
    • https://cdn.shopify.com/s/files/1/0435/5942/0063/files/lulelizopod.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_off00009b61.bin
82baa9b73906c0b8cb9d991441dfae271b3d938d5b7c64eb28935e54904771d0
pdf-font-stream PDF embedded font (sfnt) at offset 0x9B61 5492 bytes
font_01_sfnt_off0000ae0d.bin
0a3c0a643ea9bd6793f1072e2612a8962a8e7721a7b39264cb1fef130f2f41c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE0D 15748 bytes