Malicious PDF — malware analysis report

Static analysis result for SHA-256 d843b788fe1cf0f2…

MALICIOUS

PDF

74.2 KB Created: 2021-09-20 00:02:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fa0b8ef98b1701f77f4847dd7634eb9d SHA-1: fa74a849fa8bcf0e4e03e910e283efaf7d988057 SHA-256: d843b788fe1cf0f287ec0371595cf30689b9e1cb4efe11fcc8582e52c1469420
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. These links are likely intended to lure users into downloading further malware or engaging in phishing activities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 http://fongyoskert.hu/userfiles/files/90384930424.pdf In PDF document text
    • http://tdsns.ru/userfiles/file/zoramijisibavobok.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/47966614863.pdfIn PDF document text
    • http://dailygiasi.com/uploads/userfiles/file/54665402986.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613259e718fb5---xofirawazogovifaxobujavi.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/2t51aafn6ufspjchn4a2prlj8m/6419695089.pdfIn PDF document text
    • https://suadienlanhhanoi.net/upload/files/ramulogogivoxiresupuwuw.pdfIn PDF document text
    • http://benly-carson.com/product/files/77124767685.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b2cf8680a---23258501694.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/jukag.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210917034906.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/32502936831.pdfIn PDF document text
    • http://suliaox.com/v15/Upload/file/20219131016436404.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/cjo87ue43gand63miaacsqlf06/93098926371.pdfIn PDF document text
    • http://velo.hu/UserFiles/file/68133465933.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/42653781391.pdfIn PDF document text
    • http://fuguchair.com/upfolder/e/files/20210919130253.pdfIn PDF document text
    • https://panama4d.com/contents/files/mibiru.pdfIn PDF document text
    • http://lmalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69266439457.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/15008009481.pdfIn PDF document text
    • http://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/74834121356.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=update+android+10+redmi+note+8PDF link annotation
    • 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_off0000b675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB675 20268 bytes
SHA-256: 236be3914e93f2049b4970984e089f7153d8d657ada86452f763e3df3ffc8b98
font_01_sfnt_off0000eb12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB12 10728 bytes
SHA-256: f14730efb20ff476c2b289575620e865cf0887cd6ea379388e5a6206412c2b43
font_02_sfnt_off000103b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1