Malicious PDF — malware analysis report

Static analysis result for SHA-256 710ba3dccac524a1…

MALICIOUS

PDF

88.8 KB Created: 2021-09-11 05:11:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a43d3d8d1e0eb4f33b0109ee5923795 SHA-1: 2f443fa6f41a64cffc43d72bfc982fff64bf2a16 SHA-256: 710ba3dccac524a19ed0cdd77b91762bd1278696cd48cdc155c937dbf73453d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to various domains, many of which are hosted on disposable or compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish users or lead them to malicious content. The structure suggests a link farm designed to obscure the ultimate destination of the user's click.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/3a9ff126abeeda504fee4e84c5a79161/xunagoniz.pdf
    • http://axi-hohenstein.de/userfiles/file/bubaluzulirevirarukofi.pdf
    • https://ms1oke.com/contents/files/vogatevupepuzuzugorolitij.pdf
    • https://ascii.tn/web/cgi/file/4044784193.pdf
    • http://kunbot.com/upload/files/vabonedevisimo.pdf
    • http://tk-weld.com/images/library/File/2138165622.pdf
    • http://londonjip.com/userData/board/file/wokaxedap.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161344d4611850---rasewolele.pdf
    • http://preiswerte-unterkunft-papenburg.de/mediapool/96388363970.pdf
    • http://cyc.cz/pictures/clanky/files/wowebibiwim.pdf
    • https://loppisidjupdalen.se/images/uploaded/file/rezadesitad.pdf
    • http://ebslang.net/_UploadFile/Images/file/zomivuzozode.pdf
    • http://gzbaosui.com/uploadfile/files/zusuguwukiju.pdf
    • https://akamercedes.com/images/uploads/files/dorerezapuk.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d4520e32a---zorodilapamokopusanetexu.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/7cf243c04e90af3b55e33db4ebec721e/45742389160.pdf
    • http://stagelight.pl/userfiles/files/1187138691.pdf
    • http://konferencii.org/web/uploads/assets/file/kuxejudenarazaxi.pdf
    • http://uniradioweb.info/userfiles/files/78426041111.pdf
    • http://miryangpension.com/FileData/ckfinder/files/20210906_CC8CEE168365BAD8.pdf
    • http://yesilderecine.com/admin/editor_resim/file/bebipaxituwilaxufewoxu.pdf
    • http://ccsl.asia/files/rimawijoroselujusakipu.pdf
    • http://www.binghan.my/userfiles/file/witeramodixobagej.pdf
    • http://piotrkowska77.pl/zdjeciafile/62428755088.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=10+free+instagram+likes+no+trial
    • 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://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_off0000f7ce.bin
322b280f421f03279a8d5c2febf7e2df8c37ddb9f8c43f961a13fc87551dbd53
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7CE 10724 bytes
font_01_sfnt_off00011073.bin
e0ef5bcbb3897a911cc048f67f887e3dd41b04b64d004b151eef09b1b4a1ef29
pdf-font-stream PDF embedded font (sfnt) at offset 0x11073 17816 bytes
font_02_sfnt_off00013da7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DA7 16792 bytes