Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7659ee0512797a9…

MALICIOUS

PDF

67.0 KB Created: 2021-09-02 19:33:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ef0253421df9702c6174fc4e3b4dfe74 SHA-1: 72d43d6977a75febeddcc9b40b8271f463729271 SHA-256: b7659ee0512797a941b70fd36ce16f966bad2350a5f4452e88f081625316c81b
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories, indicating a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites or download further malware. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm heuristics and external URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cafepiolho.com/uploads/assets/zixejakegivulokalafewaduv.pdf In PDF document text
    • http://geredekombiservisi.com/userfiles/file/bibow.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/nexatafotakibazisenufo.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/garugutebemivonilabeji.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/ruleposezixanikuwusuva.pdfIn PDF document text
    • http://childhood-matters.com/clients/49507/File/81335222744.pdfIn PDF document text
    • http://orvosvalaszto.hu/uploads/files/fikagekutisuxed.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/61850895888.pdfIn PDF document text
    • https://marljivo.hr/UserFiles/files/pobaxivudodewoxesotu.pdfIn PDF document text
    • http://xn--2e0b95unoa536adofm5h.com/userfiles/file/2118310754.pdfIn PDF document text
    • https://arerp.kr/data/file///6429018069.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/kavumutifepoduwusidenux.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-7/20210507104832352819.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/wakuwonosopilekasagufogo.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160a38fedb4e66---rabigalex.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/lejijamilujuzizukud.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/87a1fb9ef5ee71d141ccedf47b30e44e/31652752117.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/td5nd04b0ba7p52nsrepkubp4b/46646874643.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/42693138543.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bce8268674---kozalumogix.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/winowedotejozikaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=amides+and+amines+pdfPDF 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_off0000ac3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC455 10276 bytes
SHA-256: 1da34e7888bb25d49b8605a135a786cf5763fea5b1f302d4c6606586133973ca
font_02_sfnt_off0000db5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB5D 14444 bytes
SHA-256: 3de45c9c1873b4e785ed94d9d247a105cdc3db109d07963dc01a5bf0eea45ffd