Malicious PDF — malware analysis report

Static analysis result for SHA-256 66ccdd3fdef5b8ad…

MALICIOUS

PDF

83.5 KB Created: 2021-09-02 08:20:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 82dcf389bb819b79218bd76a696dd775 SHA-1: bb573888ff19bf2c61133e09dfad7670c8538664 SHA-256: 66ccdd3fdef5b8ad0742babd536ec63264dffbff9687c837dd0525f7e0e54f2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that contains numerous external links, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://queure.ru/uplcv?utm_term=the+witches+ball
    • http://torgoborud.org/images/file/3796575527.pdf
    • http://drive4smilesontario.com/clients/e/ed/ed023a0734c265ca673a92d1d81de675/File/81109982783.pdf
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/t7ttc0nejs240bdnlmq6hpdmii/99096542273.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/0qk2bk5i9kbf1gea7mlma3qin6/43128280150.pdf
    • http://mazdooradda.com/userfiles/file/60702293487.pdf
    • http://chanakyaaerospacedefence.com/userfiles/file/92326843544.pdf
    • http://akkoryazilim.com/userfiles/file/1572230018.pdf
    • http://hotelniagararimini.eu/userfiles/files/saridiroxobivafozifiv.pdf
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/ae5bm81k76i4ld67orulkvcpl4/zesugupoma.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/crvv0fdobkh4q3c0dkupga6et5/89564935940.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608395c06ea81---vemaz.pdf
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/35824345173.pdf
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/fidokotefibolijepigivipu.pdf
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/cf090a1a81d8d9e39d780499fba77017/lufokoruxewo.pdf
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b41f9b1a35---7653041764.pdf
    • http://dental-forum.ru/userfiles/file/lerapizutejusemafelibobi.pdf
    • http://dabaizhongxue.com/upload_fck/file/2021-5-31/20210531043354649653.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/16075ab97a1313---86919046466.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608f15258225b---nonuzaxinabifunosuxi.pdf
    • http://www.serenissimaservizi.com//files/zamalufobidajujuxigu.pdf
    • http://homeopathyhongkong.org/files/73480056529.pdf
    • http://snsi.jp/image/news_file/zupekezemosizutepawodi.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9204777091---zotugovupibozazuwoxokil.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a45eda988c8---91221602391.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b6146db9d01350eebec428b1916d6a30/47712729926.pdf
    • 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_off0000e557.bin
1ee375546dd3e7559d52ce4b54ba720cec2d22f3a125317af0c4fa3e39d4c2cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xE557 16632 bytes
font_01_sfnt_off00011035.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11035 16792 bytes
font_02_sfnt_off0001284c.bin
6df802b43cd581ae22aa024d656f7578c620e3dc96f70246dba6893f56ec17fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1284C 10192 bytes