Malicious PDF — malware analysis report

Static analysis result for SHA-256 a68b7ea0d9967908…

MALICIOUS

PDF

79.8 KB Created: 2021-09-23 20:46:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 133a7cf96c2c61817ac90a1223320e26 SHA-1: 4e802ab8ce994b0e7d257139ee065fced18310cd SHA-256: a68b7ea0d996790808fc170034c1c543275d3f69d1eed50e4f25ea9b809e1a0b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs that point to various domains, many of which are hosted on disposable or compromised infrastructure. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is a link farm designed to redirect users to potentially harmful content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://oniceh.ru/uplcv?utm_term=background+images+for+android PDF link annotation
    • https://tunhuaduytan.com/upload/userfiles/files/27170352668.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/fejomeparefevovi.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/witemopitedasevezarubuf.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b358c6a688---7629063365.pdfIn PDF document text
    • http://obras.ru/sites/default/files/uploads/30472611877.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614547be27ade---rigozevexiro.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/11/jonitanesiruxorugiwin.pdfIn PDF document text
    • http://status.cz/UserFiles/File/domovubugovivof.pdfIn PDF document text
    • http://dailymaytrogiang.com/userfiles/files/zigowexusutim.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/kelixunelirilizotu.pdfIn PDF document text
    • https://sonntag-immobilien.lu/userfiles/files/lusatuzoxogajobizolid.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/kevifokemuworila.pdfIn PDF document text
    • http://queenart.kr/userData/board/file/vavaminoti.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/wirozorerogojurodusiba.pdfIn PDF document text
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/vofebevafepevum.pdfIn PDF document text
    • https://chief-moving.com/editor_upload/file/gabexokozoxegajuj.pdfIn PDF document text
    • https://ristovski.mk/public_html/upload/userfiles/file/93883162378.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/89883942013.pdfIn PDF document text
    • http://ubytovna-krumlov.cz/userfiles/file/13002301006.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/2291faa007ebc6906a0bf65257ce5555/powaroduselugifasasanema.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/82971725831.pdfIn PDF document text
    • https://mimpisiluman.com/contents/files/boratarafesasuguli.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210914_FE73D55CD145E5DB.pdfIn PDF document text
    • http://wish-pharma.com/upload/files/91120196325.pdfIn PDF document text
    • https://udruga-invalida.hr/files/gozibivosevazekujozetude.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d48a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9C 16708 bytes
SHA-256: 8bd58aff31168bc7c9723343932af8124a0ccefb416528ce8bb8278caac89a62
font_02_sfnt_off00011802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11802 10920 bytes
SHA-256: 5dcea65e5ab55e51a71f9546f5fd1d2aa9f4adfe204b9b22aaf776007f4099dd