Malicious PDF — malware analysis report

Static analysis result for SHA-256 9878399cf0ac7cf1…

MALICIOUS

PDF

80.6 KB Created: 2021-09-19 18:25:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 792c79fbab586449e548165f74dc8d53 SHA-1: af1f33fb95c307ba12464c33694b6b3dbb18556b SHA-256: 9878399cf0ac7cf1e583565de3a8cd487d0ae67fd8e08440f2cb32f6e4094d53
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document functions as a link farm, likely intended to redirect users to malicious content or phishing sites. The presence of multiple external URIs and compromised CMS upload links further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://infrive.ru/uplcv?utm_term=forza+horizon+2+apk+android PDF link annotation
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/ab65b076106b5c7971ffcda23f82ff24/69201971356.pdfIn PDF document text
    • http://qishuochem.com/siicea/userfiles/file/nolub.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/59433260248.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/22701445010.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/31255944933.pdfIn PDF document text
    • https://mexico-airport-transfers.com/ckfinder/userfiles/files/pepiba.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/71899851782.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/sivijobavapo.pdfIn PDF document text
    • http://dongphat.net/upload/files/bawumizimisajeg.pdfIn PDF document text
    • https://kottayammedicalcollege.org/CMS/ckfinder/userfiles/files/88727333140.pdfIn PDF document text
    • http://realestatemiami.com/userfiles/files/koteb.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/48786778893.pdfIn PDF document text
    • http://ags-sib.ru/ckfinder/userfiles/files/28440177708.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614009d69a5a7---65959861516.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210910100115.pdfIn PDF document text
    • http://becskeicsodajo.hu/admin/fck_upload/file/69261942681.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/gojusupadiwo.pdfIn PDF document text
    • http://svx.su/ffile/file/2478621566.pdfIn PDF document text
    • http://djapm.com/userfiles/file/gikudivovufugezewabu.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/sibulifezeluj.pdfIn PDF document text
    • http://laros.cz/UserFiles/file/rejumenupoxa.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614366c6a8546---83685952472.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210916_75F785782D11F39A.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_off0000d72e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD72E 10296 bytes
SHA-256: 0940e6c5eac6bdd00a3e2751430e773b58c2b498cf5ff080295d051b9ea6b361
font_01_sfnt_off0000ee41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE41 18012 bytes
SHA-256: 4341adf95d6f6d8adf33512a54b4a44056ec2abe534d253b0e01132113ba59f7
font_02_sfnt_off00011c8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1