Malicious PDF — malware analysis report

Static analysis result for SHA-256 5679a3dd97ac49c3…

MALICIOUS

PDF

40.8 KB Created: 2020-08-31 01:59:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e51f3118974853d4c46fff3e7eac0aa5 SHA-1: 4a2ffc6f3c07fa942986c55d026bb49fbea778f9 SHA-256: 5679a3dd97ac49c3a51e97028754a6af083b5484839b7c236017ff871f7f200a
154 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded links, identified as a link farm. One of these links, 'https://ttraff.com/wix?keyword=la+familia+worksheet+answers', points to known malicious redirector infrastructure. The document body, though heavily obfuscated, also contains this URL, suggesting it is the primary lure. The presence of numerous other links to external PDFs, many hosted on static.usrfiles.com, indicates a coordinated effort to distribute content or traffic through these redirects.

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.com/wix?keyword=la+familia+worksheet+answers
    • https://static.usrfiles.com/ugd/739437_321cc0b6735646c6bdf10206ecf4ba6d.pdf
    • https://static.usrfiles.com/ugd/7f929b_14f01aebba304f83a0c5a42feb596afe.pdf
    • https://static.usrfiles.com/ugd/b4609a_9a1e9ad5437145488d21f686a87dc86f.pdf
    • https://static.usrfiles.com/ugd/95089d_aa23d6c9a6334b72b09a50a3b121d8dd.pdf
    • https://static.usrfiles.com/ugd/9ea9b6_8c66b892461045fb9529536acd9e4d1e.pdf
    • https://cdn.shopify.com/s/files/1/0428/8158/1209/files/95267478394.pdf
    • https://cdn.shopify.com/s/files/1/0433/7264/2460/files/98185648117.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9207/files/22723577559.pdf
    • https://cdn.shopify.com/s/files/1/0431/2812/7650/files/rakalebivavez.pdf
    • https://cdn.shopify.com/s/files/1/0428/9911/2099/files/mobarezu.pdf
    • https://static.usrfiles.com/ugd/b7082a_f77374fba44848b0a01a1131daa138f4.pdf
    • https://static.usrfiles.com/ugd/b8c837_eb337cc5f30340fc93be43de54c95934.pdf
    • https://static.usrfiles.com/ugd/b8c837_a81dc73f478046abb8e658efe26eccdc.pdf
    • https://static.usrfiles.com/ugd/bb13a2_37805ec0438b44dc9cb4cbd223e68467.pdf
    • https://static.usrfiles.com/ugd/a31856_189f026978734e6888b44fb3236e6739.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_off00006290.bin
48ab388c7e4b294b449ad156370e61824a6d92fad60f844ebb32f5502fbb6d00
pdf-font-stream PDF embedded font (sfnt) at offset 0x6290 5104 bytes
font_01_sfnt_off000073e1.bin
baef96203ec6e04a0a1e97768af04be0041e0da77540d308469e631533d7be55
pdf-font-stream PDF embedded font (sfnt) at offset 0x73E1 10120 bytes