Malicious PDF — malware analysis report

Static analysis result for SHA-256 d81de13b4a62cd63…

MALICIOUS

PDF

48.4 KB Created: 2020-11-09 12:33:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 64fb946595e573a368f75e137570a859 SHA-1: 117e06ded947a65bd0ff4f9c5f9e2bd7cf668f63 SHA-256: d81de13b4a62cd63cb55680158902f3560822b1cb8df6faa1a7de0b19522ad22
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded URLs and a heuristic firing indicates a link farm, suggesting an attempt to drive traffic to external sites. The document body, though heavily obfuscated, contains a URL that appears to be part of a lure. The ML classifier strongly indicates maliciousness, and the presence of external links points towards a phishing or SEO spam attack.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://trafficel.ru/123?keyword=algona+middle+school+algona
    • https://cdn-cms.f-static.net/uploads/4371025/normal_5fa4a824c8af4.pdf
    • https://dujaporugegebo.weebly.com/uploads/1/3/4/3/134314108/0781e21.pdf
    • https://cdn-cms.f-static.net/uploads/4375073/normal_5fa126363e785.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/sodoxi/ymca_lifeguard_test_a_answers.pdf
    • https://uploads.strikinglycdn.com/files/c898093c-3598-4fc1-804e-5b62cc69ddff/52024117525.pdf
    • https://s3.amazonaws.com/novipaliwid/kulolijowisipuzu.pdf
    • https://s3.amazonaws.com/robumuduluwise/how_do_cannonball_jellyfish_reproduce.pdf
    • https://uploads.strikinglycdn.com/files/0a1d1a43-2486-45a0-96f3-d1a081ab7b91/bejuxasozexedi.pdf
    • https://uploads.strikinglycdn.com/files/81a56c97-5cd1-4bed-b419-0a308fd767e3/14303337981.pdf
    • https://s3.amazonaws.com/tibitexil/fipexaniku.pdf
    • https://uploads.strikinglycdn.com/files/53f8d21d-0354-46e4-9373-d75dcf280967/duxapa.pdf
    • https://uploads.strikinglycdn.com/files/db45bd0e-b44d-4446-83ca-4e38f72cdc92/baxuxajagexoso.pdf
    • https://uploads.strikinglycdn.com/files/14a183be-58ce-4cf5-b149-102903e12ecf/24825359386.pdf
    • https://s3.amazonaws.com/zinudipir/1801479196.pdf
    • https://s3.amazonaws.com/towutoginadivu/denosus.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/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006721.bin
2fa2c4bd38c1a5476823026efb887212de43a88f95224f30cf498580291a9e31
pdf-font-stream PDF embedded font (sfnt) at offset 0x6721 5248 bytes
font_01_sfnt_off000078d4.bin
ad4f7ab7c618440966268d28388e77ecd3054b3837a0f6f75f71f5eef7b95595
pdf-font-stream PDF embedded font (sfnt) at offset 0x78D4 10060 bytes
font_02_sfnt_off00009b78.bin
8b09c1815870b273a56f0e8fd73df238545ca9f7b8d5494693e98dbb1165f92a
pdf-font-stream PDF embedded font (sfnt) at offset 0x9B78 17032 bytes